Vehicle assisted harpoon breaching tool

DOEpatents

Pacheco, James E [Albuquerque, NM; Highland, Steven E [Albuquerque, NM

2011-02-15

A harpoon breaching tool that allows security officers, SWAT teams, police, firemen, soldiers, or others to forcibly breach metal doors or walls very quickly (in a few seconds), without explosives. The harpoon breaching tool can be mounted to a vehicle's standard receiver hitch.

Religion, fertility and genes: a dual inheritance model

PubMed Central

Rowthorn, Robert

2011-01-01

Religious people nowadays have more children on average than their secular counterparts. This paper uses a simple model to explore the evolutionary implications of this difference. It assumes that fertility is determined entirely by culture, whereas subjective predisposition towards religion is influenced by genetic endowment. People who carry a certain ‘religiosity’ gene are more likely than average to become or remain religious. The paper considers the effect of religious defections and exogamy on the religious and genetic composition of society. Defections reduce the ultimate share of the population with religious allegiance and slow down the spread of the religiosity gene. However, provided the fertility differential persists, and people with a religious allegiance mate mainly with people like themselves, the religiosity gene will eventually predominate despite a high rate of defection. This is an example of ‘cultural hitch-hiking’, whereby a gene spreads because it is able to hitch a ride with a high-fitness cultural practice. The theoretical arguments are supported by numerical simulations. PMID:21227968

Religion, fertility and genes: a dual inheritance model.

PubMed

Rowthorn, Robert

2011-08-22

Religious people nowadays have more children on average than their secular counterparts. This paper uses a simple model to explore the evolutionary implications of this difference. It assumes that fertility is determined entirely by culture, whereas subjective predisposition towards religion is influenced by genetic endowment. People who carry a certain 'religiosity' gene are more likely than average to become or remain religious. The paper considers the effect of religious defections and exogamy on the religious and genetic composition of society. Defections reduce the ultimate share of the population with religious allegiance and slow down the spread of the religiosity gene. However, provided the fertility differential persists, and people with a religious allegiance mate mainly with people like themselves, the religiosity gene will eventually predominate despite a high rate of defection. This is an example of 'cultural hitch-hiking', whereby a gene spreads because it is able to hitch a ride with a high-fitness cultural practice. The theoretical arguments are supported by numerical simulations.

Modularity, Working Memory and Language Acquisition

ERIC Educational Resources Information Center

Baddeley, Alan D.

2017-01-01

The concept of modularity is used to contrast the approach to working memory proposed by Truscott with the Baddeley and Hitch multicomponent model. This proposes four sub components comprising the "central executive," an executive control system of limited attentional capacity that utilises storage based on separate but interlinked…

A Hitch-Hiker's Guide to the World of Videotex.

ERIC Educational Resources Information Center

Bacsich, Paul D.; Castro, Angela S.

Pointing out that the term "videotex" is a general term covering three types of videotex systems, i.e., teletext, viewdata, and cable text, this paper briefly describes such systems and notes that their future depends on social acceptance and permeation as well as government regulations. The difficulties for international videotex…

Genetic hitch-hiking extends the range of coast live oak

Treesearch

Richard S. Dodd; Zara Afzal-Rafii; Wasima Mayer

2006-01-01

The northernmost range of coast live oak (Quercus agrifolia) is reported from the Ukiah Valley (Mendocino County, California). Here, field observations suggest that hybridization with interior live oak (Q. wislizeni) is important. Elsewhere in northern California, morphology of coast live oak can be highly variable (particularly...

Discrimination against Facially Stigmatized Applicants in Interviews: An Eye-Tracking and Face-to-Face Investigation

ERIC Educational Resources Information Center

Madera, Juan M.; Hebl, Michelle R.

2012-01-01

Drawing from theory and research on perceived stigma (Pryor, Reeder, Yeadon, & Hesson-McInnis, 2004), attentional processes (Rinck & Becker, 2006), working memory (Baddeley & Hitch, 1974), and regulatory resources (Muraven & Baumeister, 2000), the authors examined discrimination against facially stigmatized applicants and the processes involved.…

Rescue Manual. Module 4.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. Instructional Materials Lab.

This learner manual for rescuers covers the current techniques or practices required in the rescue service. The fourth of 10 modules contains 8 chapters: (1) construction and characteristics of rescue rope; (2) knots, bends, and hitches; (3) critical angles; (4) raising systems; (5) rigging; (6) using the brake-bar rack for rope rescue; (7) rope…

European Glaucoma Society Terminology and Guidelines for Glaucoma, 4th Edition - Part 1Supported by the EGS Foundation

PubMed Central

2017-01-01

Foreword It gives me pleasure to introduce the 4th edition of the EGS Guidelines. The Third edition proved to be extremely successful, being translated into 7 languages with over 70000 copies being distributed across Europe; it has been downloadable, free, as a pdf file for the past 4 years. As one of the main objectives of the European Glaucoma Society has been to both educate and standardize glaucoma practice within the EU, these guidelines were structured so as to play their part. Glaucoma is a living specialty, with new ideas on causation, mechanisms and treatments constantly appearing. As a number of years have passed since the publication of the last edition, changes in some if not all of these ideas would be expected. For this new edition of the guidelines a number of editorial teams were created, each with responsibility for an area within the specialty; updating where necessary, introducing new diagrams and Flowcharts and ensuring that references were up to date. Each team had writers previously involved with the last edition as well as newer and younger members being co-opted. As soon as specific sections were completed they had further editorial comment to ensure cross referencing and style continuity with other sections. Overall guidance was the responsibility of Anders Heijl and Carlo Traverso. Tribute must be made to the Task Force whose efforts made the timely publication of the new edition possible. Roger Hitchings Chairman of the EGS Foundation www.eugs.org The Guidelines Writers and Contributors  Augusto Azuara Blanco Luca Bagnasco Alessandro Bagnis Keith Barton Christoph Baudouin Boel Bengtsson Alain Bron Francesca Cordeiro Barbara Cvenkel Philippe Denis Christoph Faschinger Panayiota Founti Stefano Gandolfi David Garway Heath Francisco Goni Franz Grehn Anders Heijl Roger Hitchings Gabor Hollo Tony Hommer Michele Iester Jost Jonas Yves Lachkar Giorgio Marchini Frances Meier Gibbons Stefano Miglior Marta Misiuk-Hojo Maria Musolino Jean Philippe Nordmann Norbert Pfeiffer Luis Abegao Pinto Luca Rossetti John Salmon Leo Schmetterer Riccardo Scotto Tarek Shaarawy Ingeborg Stalmans Gordana Sunaric Megevand Ernst Tamm John Thygesen Fotis Topouzis Carlo Enrico Traverso Anja Tuulonen Ananth Viswanathan Thierry Zeyen The Guidelines Task Force  Luca Bagnasco Anders Heijl Carlo Enrico Traverso Augusto Azuara Blanco Alessandro Bagnis David Garway Heath Michele Iester Yves Lachkar Ingeborg Stalmans Gordana Sunaric Mégevand Fotis Topouzis Anja Tuulonen Ananth Viswanathan The EGS Executive Committee  Carlo Enrico Traverso (President) Anja Tuulonen (Vice President) Roger Hitchings (Past President) Anton Hommer (Treasurer) Barbara Cvenkel Julian Garcia Feijoo David Garway Heath Norbert Pfeiffer Ingeborg Stalmans The Board of the European Glaucoma Society Foundation  Roger Hitchings (Chair) Carlo E. Traverso (Vice Chair) Franz Grehn Anders Heijl John Thygesen Fotis Topouzis Thierry Zeyen The EGS Committees  CME and Certification  Gordana Sunaric Mégevand (Chair) Carlo Enrico Traverso (Co-chair) Delivery of Care  Anton Hommer (Chair) EU Action  Thierry Zeyen (Chair) Carlo E. Traverso (Co-chair) Education  John Thygesen (Chair) Fotis Topouzis (Co-chair) Glaucogene  Ananth Viswanathan (Chair) Fotis Topouzis (Co-chair) Industry Liaison  Roger Hitchings (Chair) Information Technology  Ingeborg Stalmans (Chair) Carlo E. Traverso (Co-chair) National Society Liaison  Anders Heijl (Chair) Program Planning  Fotis Topouzis (Chair) Ingeborg Stalmans (Co-chair) Quality and Outcomes  Anja Tuulonen (Chair) Augusto Azuara Blanco (Co-chair) Scientific  Franz Grehn (Chair) David Garway Heath (Co-chair) PMID:27378485

Musicians' Memory for Verbal and Tonal Materials under Conditions of Irrelevant Sound

ERIC Educational Resources Information Center

Williamson, Victoria J.; Mitchell, Tom; Hitch, Graham J.; Baddeley, Alan D.

2010-01-01

Studying short-term memory within the framework of the working memory model and its associated paradigms (Baddeley, 2000; Baddeley & Hitch, 1974) offers the chance to compare similarities and differences between the way that verbal and tonal materials are processed. This study examined amateur musicians' short-term memory using a newly adapted…

Commitments to Improve the Quality of Learning.

ERIC Educational Resources Information Center

Cross, K. Patricia

For the nation as a whole, there is a moving bandwagon of educational change, clearly hitched to attempts to personalize and individualize instruction. The new emphases on the quality of learning appears to offer some potential solutions to two current problems: the twin problems of quality and equality in education. Traditional group-oriented…

Summary Report of Finding of the Decision Science Working Group (DSWG)

DTIC Science & Technology

2006-06-01

Seminar Attendance List White Eagle Conference Center Hamilton, NY 5-7 Aug 2003 Alvarez, Rebecca C., Civ, AFRL/IFSB Barsch, Kurt W. 2Lt, AFRL...Gemelli, Nathaniel, Civ, AFRL/IFTB Hitchings, John E., Civ, AFRL/IFSA Hwang, Jong S., Civ, AFRL/IFSD Hwang, Victoria Y., Civ, AFRL/IFSA Kremer , Gul, PSU

Exploration of a "Double-Jeopardy" Hypothesis within Working Memory Profiles for Children with Specific Language Impairment

ERIC Educational Resources Information Center

Briscoe, J.; Rankin, P. M.

2009-01-01

Background: Children with specific language impairment (SLI) often experience difficulties in the recall and repetition of verbal information. Archibald and Gathercole (2006) suggested that children with SLI are vulnerable across two separate components of a tripartite model of working memory (Baddeley and Hitch 1974). However, the hierarchical…

KSC-2009-3467

NASA Image and Video Library

2009-06-01

CAPE CANAVERAL, Fla. – Hitching a ride on the Shuttle Carrier Aircraft, or SCA, a modified Boeing 747, space shuttle Atlantis has landed at Columbus Air Force Base in Mississippi for a fuel stop on its journey back to Florida. Atlantis' next assignment is the STS-129 mission, targeted to launch in November 2009. Photo credit: NASA/Ben Smegelsky

KSC-2009-3468

NASA Image and Video Library

2009-06-01

CAPE CANAVERAL, Fla. – Hitching a ride on the Shuttle Carrier Aircraft, or SCA, a modified Boeing 747, space shuttle Atlantis has landed at Columbus Air Force Base in Mississippi for a fuel stop on its journey back to Florida. Atlantis' next assignment is the STS-129 mission, targeted to launch in November 2009. Photo credit: NASA/Ben Smegelsky

Hitch Your Wagon to a Mission Statement

ERIC Educational Resources Information Center

Zmuda, Allison

2007-01-01

Library media specialists typically are expected to collaborate with everyone. Because the teacher holds the proverbial key to the classroom door, he or she also has the access to the students. If there is no access to students, there is no opportunity to cause student learning. Real collaboration is, in contrast, based on a mutual understanding…

Managing Large-Enrollment Courses in Hybrid Instruction Mode

ERIC Educational Resources Information Center

Khanna, Pooja

2016-01-01

This essay addresses the hitches and glitches in the hybrid instruction system of teaching and learning for large-enrollment courses. This new instructional methodology asks facilitators to redesign their entire traditional teaching and learning practices. The nature of subject to be taught via the hybrid mode further affects the success rate of…

Material flow analysis of scarce metals: sources, functions, end-uses and aspects for future supply.

PubMed

Peiró, Laura Talens; Méndez, Gara Villalba; Ayres, Robert U

2013-03-19

A number of metals that are now important to the electronic industry (and others) will become much more important in the future if current trends in technology continue. Most of these metals are byproducts (or hitch-hikers) of a small number of important industrial metals (attractors). By definition, the metals in the hitch-hiker group are not mined by themselves, and thus their production is limited by the demand for the major attractors. This article presents a material flow analysis (MFA) of the complex inter-relationships between these groups of metals. First, it surveys the main sources of geologically scarce (byproduct) metals currently considered critical by one or other of several recent studies. This is followed by a detailed survey of their major functions and the quantities contained in intermediate and end-products. The purpose is to identify the sectors and products where those metals are used and stocked and thus potentially available for future recycling. It concludes with a discussion of the limitations of possible substitution and barriers to recycling.

A Revised Model of Short-Term Memory and Long-Term Learning of Verbal Sequences

ERIC Educational Resources Information Center

Burgess, Neil; Hitch, Graham J.

2006-01-01

The interaction between short- and long-term memory is studied within a model in which phonemic and (temporal) contextual information have separate influences on immediate verbal serial recall via connections with short- and long-term plasticity [Burgess, N., & Hitch, G.J. (1999). Memory for serial order: a network model of the phonological loop…

Effective Communication Is "Hitched to Everything in the (Business) Universe"

ERIC Educational Resources Information Center

Krajicek, John

2008-01-01

The author of this article is an English teacher and a certified public accountant at the same time. When he was offered a position teaching business communication in an MBA program, he was delighted to know that he can actually dovetail his two contrasting careers. In this article, the author relates his experiences and the benefits of…

Michigan's District Focus Gets Traction: Partnership with Comprehensive Centers Provides Momentum

ERIC Educational Resources Information Center

Bailey, Bersheril; Coscarella, Mark; Kinnaman, Lisa

2012-01-01

Hitching a ride on an automotive metaphor comes easily when Michigan is at the center of the story. After the Michigan Department of Education (MDE) spent a couple years noodling in the design shop about the optimum drivers of school improvement, its education engineers were convinced that the local school district was positioned to shift the…

How It's Done: Using "Hitch" as a Guide to Uncertainty Reduction Theory

ERIC Educational Resources Information Center

Dawkins, Marcia Alesan

2010-01-01

Popular films can be important pedagogical tools in today's communication courses. Constructing classroom experiences that use film can make theory come alive for students. At the same time, theory can be used to probe deeper into the complexities of human behavior via astute film analysis. In the case of Uncertainty Reduction Theory (URT), a…

The Structure of Working Memory from 4 to 15 Years of Age

ERIC Educational Resources Information Center

Gathercole, Susan E.; Pickering, Susan J.; Ambridge, Benjamin; Wearing, Hannah

2004-01-01

The structure of working memory and its development across the childhood years were investigated in children 4-15 years of age. The children were given multiple assessments of each component of the A. D. Baddeley and G. Hitch (1974) working memory model. Broadly similar linear functions characterized performance on all measures as a function of…

KSC-2009-3466

NASA Image and Video Library

2009-06-01

CAPE CANAVERAL, Fla. – Hitching a ride on the Shuttle Carrier Aircraft, or SCA, a modified Boeing 747, space shuttle Atlantis has arrived in Lackland Air Force Base's Kelly Field Annex in Texas for a fuel stop on its journey back to Florida. Atlantis' next assignment is the STS-129 mission, targeted to launch in November 2009. Photo credit: NASA/Ben Smegelsky

GALLUPing to the POLLS or Hitching Your Bandwagon to a Slogan.

ERIC Educational Resources Information Center

Achilles, C. M.

Today's educators sometimes make unthinking hasty decisions based on a "Gallup Poll" mentality that holds that whatever the majority of the people want should be implemented. Educators, bowing to public pressure, are sometimes too quick to jump on any bandwagon. One such bandwagon is the current back to basics movement. Insofar as back…

On the Nature of Forgetting and the Processing--Storage Relationship in Reading Span Performance

ERIC Educational Resources Information Center

Saito, Satoru; Miyake, Akira

2004-01-01

Four experiments examined the nature of forgetting and the processing--storage relationship during performance on a prevalent working memory task, the reading span test. Using two different presentation paradigms, Experiments 1 and 2 replicated Towse, Hitch, and Hutton's (1998, 2000) finding that the Short-Final lists, which presented a long…

Impaired Verbal Short-Term Memory in down Syndrome Reflects a Capacity Limitation Rather than Atypically Rapid Forgetting

ERIC Educational Resources Information Center

M. Purser, H.R.; Jarrold, C.

2005-01-01

Individuals with Down syndrome suffer from relatively poor verbal short-term memory. Recent work has indicated that this deficit is not caused by problems of audition, speech, or articulatory rehearsal within the phonological loop component of Baddeley and Hitch's working memory model. Given this, two experiments were conducted to investigate…

The Gonzo Scientist. Slaying monsters for science.

PubMed

Bohannon, John

2008-06-20

Slaying Monsters for Science John Bohannon The first scientific conference held in Azeroth, the online universe of the role-playing game World of Warcraft, went off virtually without a hitch. Although the participants all died during the final day's social event - a massive raid on an enemy fort - they agree that this event is a glimpse at the future of scientific exchange.

The Limits of Visual Working Memory in Children: Exploring Prioritization and Recency Effects with Sequential Presentation

ERIC Educational Resources Information Center

Berry, Ed D. J.; Waterman, Amanda H.; Baddeley, Alan D.; Hitch, Graham J.; Allen, Richard J.

2018-01-01

Recent research has demonstrated that, when instructed to prioritize a serial position in visual working memory (WM), adults are able to boost performance for this selected item, at a cost to nonprioritized items (e.g., Hu, Hitch, Baddeley, Zhang, & Allen, 2014). While executive control appears to play an important role in this ability, the…

New York's battle with the Asian long-horned beetle

Treesearch

Robert A. Haack; Kenneth R. Law; Victor C. Mastro; H. Sharon Ossenburgen; Bernard J. Raimo

1997-01-01

A wide variety of organisms are unintentionally transported from country to country each year, primarily as a result of world trade. Practically all classes of plants and animals can be stowaways. Aquatic organisms travel in the ballast water of ships; land organisms move with the cargo. Some organisms hitch rides inside the cargo, while others travel on or inside...

Three PhoneSats Hitch Ride on Inaugural Antares Launch (Reporter Pkg)

NASA Image and Video Library

2013-04-10

Package created for JSC's launch coverage of Antares rocket launch from Wallops Flight Facility on April 17, 2013. The Orbital Sciences Corporation test flight of the Antares rocket will be carrying a very small secondary payload into space. Onboard are three nano-satellites that were designed and built at NASA Ames Research Center, the lead Center for Small Spacecraft Development.

Slave to the Rhythm: Experimental Tests of a Model for Verbal Short-Term Memory and Long-Term Sequence Learning

ERIC Educational Resources Information Center

Hitch, Graham J.; Flude, Brenda; Burgess, Neil

2009-01-01

Three experiments tested predictions of a neural network model of phonological short-term memory that assumes separate representations for order and item information, order being coded via a context-timing signal [Burgess, N., & Hitch, G. J. (1999). Memory for serial order: A network model of the phonological loop and its timing. "Psychological…

Driver assistance system for passive multi-trailer vehicles with haptic steering limitations on the leading unit.

PubMed

Morales, Jesús; Mandow, Anthony; Martínez, Jorge L; Reina, Antonio J; García-Cerezo, Alfonso

2013-04-03

Driving vehicles with one or more passive trailers has difficulties in both forward and backward motion due to inter-unit collisions, jackknife, and lack of visibility. Consequently, advanced driver assistance systems (ADAS) for multi-trailer combinations can be beneficial to accident avoidance as well as to driver comfort. The ADAS proposed in this paper aims to prevent unsafe steering commands by means of a haptic handwheel. Furthermore, when driving in reverse, the steering-wheel and pedals can be used as if the vehicle was driven from the back of the last trailer with visual aid from a rear-view camera. This solution, which can be implemented in drive-by-wire vehicles with hitch angle sensors, profits from two methods previously developed by the authors: safe steering by applying a curvature limitation to the leading unit, and a virtual tractor concept for backward motion that includes the complex case of set-point propagation through on-axle hitches. The paper addresses system requirements and provides implementation details to tele-operate two different off- and on-axle combinations of a tracked mobile robot pulling and pushing two dissimilar trailers.

Translational repression of the Drosophila nanos mRNA involves the RNA helicase Belle and RNA coating by Me31B and Trailer hitch.

PubMed

Götze, Michael; Dufourt, Jérémy; Ihling, Christian; Rammelt, Christiane; Pierson, Stephanie; Sambrani, Nagraj; Temme, Claudia; Sinz, Andrea; Simonelig, Martine; Wahle, Elmar

2017-10-01

Translational repression of maternal mRNAs is an essential regulatory mechanism during early embryonic development. Repression of the Drosophila nanos mRNA, required for the formation of the anterior-posterior body axis, depends on the protein Smaug binding to two Smaug recognition elements (SREs) in the nanos 3' UTR. In a comprehensive mass spectrometric analysis of the SRE-dependent repressor complex, we identified Smaug, Cup, Me31B, Trailer hitch, eIF4E, and PABPC, in agreement with earlier data. As a novel component, the RNA-dependent ATPase Belle (DDX3) was found, and its involvement in deadenylation and repression of nanos was confirmed in vivo. Smaug, Cup, and Belle bound stoichiometrically to the SREs, independently of RNA length. Binding of Me31B and Tral was also SRE-dependent, but their amounts were proportional to the length of the RNA and equimolar to each other. We suggest that "coating" of the RNA by a Me31B•Tral complex may be at the core of repression. © 2017 Götze et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Shape memory-based actuators and release mechanisms therefrom

NASA Technical Reports Server (NTRS)

Vaidyanathan, Rajan (Inventor); Snyder, Daniel W. (Inventor); Schoenwald, David K. (Inventor); Lam, Nhin S. (Inventor); Watson, Daniel S. (Inventor); Krishnan, Vinu B. (Inventor); Noebe, Ronald D. (Inventor)

2012-01-01

SM-based actuators (110) and release mechanisms (100) therefrom and systems (500) including one or more release mechanisms (100). The actuators (110) comprise a SM member (118) and a deformable member (140) mechanically coupled to the SM member (118) which deforms upon a shape change of the SM member triggered by a phase transition of the SM member. A retaining element (160) is mechanically coupled to the deformable member (140), wherein the retaining element (160) moves upon the shape change. Release mechanism (100) include an actuator, a rotatable mechanism (120) including at least one restraining feature (178) for restraining rotational movement of the retaining element (160) before the shape change, and at least one spring (315) that provides at least one locked spring-loaded position when the retaining element is in the restraining feature and at least one released position that is reached when the retaining element is in a position beyond the restraining feature (178). The rotatable mechanism (120) includes at least one load-bearing protrusion (310). A hitch (400) is for mechanically coupling to the load, wherein the hitch is supported on the load bearing protrusion (310) when the rotatable mechanism is in the locked spring-loaded position.

Environmental implications of plastic debris in marine settings—entanglement, ingestion, smothering, hangers-on, hitch-hiking and alien invasions

PubMed Central

Gregory, Murray R.

2009-01-01

Over the past five or six decades, contamination and pollution of the world’s enclosed seas, coastal waters and the wider open oceans by plastics and other synthetic, non-biodegradable materials (generally known as ‘marine debris’) has been an ever-increasing phenomenon. The sources of these polluting materials are both land- and marine-based, their origins may be local or distant, and the environmental consequences are many and varied. The more widely recognized problems are typically associated with entanglement, ingestion, suffocation and general debilitation, and are often related to stranding events and public perception. Among the less frequently recognized and recorded problems are global hazards to shipping, fisheries and other maritime activities. Today, there are rapidly developing research interests in the biota attracted to freely floating (i.e. pelagic) marine debris, commonly known as ‘hangers-on and hitch-hikers’ as well as material sinking to the sea floor despite being buoyant. Dispersal of aggressive alien and invasive species by these mechanisms leads one to reflect on the possibilities that ensuing invasions could endanger sensitive, or at-risk coastal environments (both marine and terrestrial) far from their native habitats. PMID:19528053

Driver Assistance System for Passive Multi-Trailer Vehicles with Haptic Steering Limitations on the Leading Unit

PubMed Central

Morales, Jesús; Mandow, Anthony; Martínez, Jorge L.; Reina, Antonio J.; García-Cerezo, Alfonso

2013-01-01

Driving vehicles with one or more passive trailers has difficulties in both forward and backward motion due to inter-unit collisions, jackknife, and lack of visibility. Consequently, advanced driver assistance systems (ADAS) for multi-trailer combinations can be beneficial to accident avoidance as well as to driver comfort. The ADAS proposed in this paper aims to prevent unsafe steering commands by means of a haptic handwheel. Furthermore, when driving in reverse, the steering-wheel and pedals can be used as if the vehicle was driven from the back of the last trailer with visual aid from a rear-view camera. This solution, which can be implemented in drive-by-wire vehicles with hitch angle sensors, profits from two methods previously developed by the authors: safe steering by applying a curvature limitation to the leading unit, and a virtual tractor concept for backward motion that includes the complex case of set-point propagation through on-axle hitches. The paper addresses system requirements and provides implementation details to tele-operate two different off- and on-axle combinations of a tracked mobile robot pulling and pushing two dissimilar trailers. PMID:23552102

Environmental implications of plastic debris in marine settings--entanglement, ingestion, smothering, hangers-on, hitch-hiking and alien invasions.

PubMed

Gregory, Murray R

2009-07-27

Over the past five or six decades, contamination and pollution of the world's enclosed seas, coastal waters and the wider open oceans by plastics and other synthetic, non-biodegradable materials (generally known as 'marine debris') has been an ever-increasing phenomenon. The sources of these polluting materials are both land- and marine-based, their origins may be local or distant, and the environmental consequences are many and varied. The more widely recognized problems are typically associated with entanglement, ingestion, suffocation and general debilitation, and are often related to stranding events and public perception. Among the less frequently recognized and recorded problems are global hazards to shipping, fisheries and other maritime activities. Today, there are rapidly developing research interests in the biota attracted to freely floating (i.e. pelagic) marine debris, commonly known as 'hangers-on and hitch-hikers' as well as material sinking to the sea floor despite being buoyant. Dispersal of aggressive alien and invasive species by these mechanisms leads one to reflect on the possibilities that ensuing invasions could endanger sensitive, or at-risk coastal environments (both marine and terrestrial) far from their native habitats.

Deriving the Cost of Software Maintenance for Software Intensive Systems

DTIC Science & Technology

2011-08-29

more of software maintenance). Figure 4. SEER-SEM Maintenance Effort by Year Report (Reifer, Allen, Fersch, Hitchings, Judy , & Rosa, 2010...understand the linear relationship between two variables. The formula for the simple Pearson product-moment correlation is represented in Equation 5...standardization is required across the software maintenance community in order to ensure that the data being recorded can be employed beyond the agency or

Rathayibacter toxicus: how a bacterium hitches a ride on a nematode to invade grass seeds and produce a toxin harmful to livestock

USDA-ARS?s Scientific Manuscript database

Rathayibacter toxicus is a forage grass associated Gram-positive bacterium of major concern to food safety and agriculture. This species is listed by USDA-APHIS as a plant pathogen select agent because it produces a tunicamycin-like toxin that is lethal to livestock and may be vectored by nematode s...

Working memory for braille is shaped by experience.

PubMed

Cohen, Henri; Scherzer, Peter; Viau, Robert; Voss, Patrice; Lepore, Franco

2011-03-01

Tactile working memory was found to be more developed in completely blind (congenital and acquired) than in semi-sighted subjects, indicating that experience plays a crucial role in shaping working memory. A model of working memory, adapted from the classical model proposed by Baddeley and Hitch1 and Baddeley2 is presented where the connection strengths of a highly cross-modal network are altered through experience.

Move to outpatient settings may boost medical hotels.

PubMed

Burns, J

1992-06-08

The shift of surgeries to outpatient settings could be healthy for medical hotels, those amenity-equipped facilities originally developed to ease patients out of costly acute-care beds. Because fewer hospitals have a pressing need to use such alternative lodging, some medical hotels are hoping to hitch their fortunes to the outpatient trade, keeping patients overnight after surgeries that don't require hospital admission.

Working memory for braille is shaped by experience

PubMed Central

Scherzer, Peter; Viau, Robert; Voss, Patrice; Lepore, Franco

2011-01-01

Tactile working memory was found to be more developed in completely blind (congenital and acquired) than in semi-sighted subjects, indicating that experience plays a crucial role in shaping working memory. A model of working memory, adapted from the classical model proposed by Baddeley and Hitch1 and Baddeley2 is presented where the connection strengths of a highly cross-modal network are altered through experience. PMID:21655448

Towards a Fiscally Constrained Pacific Posture

DTIC Science & Technology

2012-03-21

joint press conference with Australian Prime Minister Julia Gillard , President Obama emphasized U.S. intent in the Asia Pacific region when he... gillard -australia-joint-press (accessed February 5, 2012). 5 Laura MacInnis and Caren Bohan, “Obama seeks to hitch U.S. economy to Asian growth,” Reuters...November 16, 2011. http://www.whitehouse.gov/the-press-office/2011/11/16/remarks-president-obama-and-prime- minister- gillard -australia-joint-press

MS Musgrave handled hardware in the FWD MDDK

NASA Image and Video Library

2014-04-09

51F-13-021 (29 July-6 Aug 1985) --- Astronaut Story Musgrave, STS51F mission specialist, is seen hitching a zero-g ride on a blood centrifuge on the middeck of the space shuttle Challenger. "The centrifuge got more workout than just separation of our blood," crewmate John Bartoe, payload specialist, later told a gathering of media representatives at the 51F post-flight press conference, referring to Musgrave's off-duty antics. Photo credit: NASA

Workplace loyalty in the 1990s.

PubMed

Umiker, W

1995-03-01

The loyalty paradigm is evolving as part of our cultural modifications. We must enunciate our own standards and temper them with realism. Employers can seldom promise permanent jobs, and employees are reluctant to hitch their stars to one organization. In health care institutions, ethical considerations may result in divergent allegiances. The new loyalty paradigm is affected by the movements toward participative management and team building. A number of suggestions are offered for enhancing a pragmatic form of loyalty.

JPRS Report, Near East & South Asia.

DTIC Science & Technology

1989-07-10

you only seconds to get a number in Baghdad and other provinces from al-Basrah without any hitches". He also spoke of new plans to increase...covered his eyes, muttered a few exclamations of surprise, and laughed. [YEDI’OT] But what do you have against Mina Tze- mah? [Rabbi...condemned the Sicarites. [Rabbi] "Yes? Where?" [YEDI’OT] I heard him. [Rabbi] "Are you sure?" A few minutes after it was announced that the

Defense Planning in the Ministry of Defense of Ukraine: Decade of Attempts and Mistakes

DTIC Science & Technology

2015-06-01

Defense. (University of California Press, Berkeley and Los Angeles , 1967). 22 but due to the Soviet Union basis system, it is not as efficient in...Making for Defense. University of California Press, Berkeley and Los Angeles , 1967. Hitch, Charles Johnston and Roland N. McKean. The Economics of...loss of defense is not an instantaneous phenomenon. This phenomenon has led to human disorder, blind and continuous personnel downsizing, reform of the

Subcellular localization of transiently expressed fluorescent fusion proteins.

PubMed

Collings, David A

2013-01-01

The recent and massive expansion in plant genomics data has generated a large number of gene sequences for which two seemingly simple questions need to be answered: where do the proteins encoded by these genes localize in cells, and what do they do? One widespread approach to answering the localization question has been to use particle bombardment to transiently express unknown proteins tagged with green fluorescent protein (GFP) or its numerous derivatives. Confocal fluorescence microscopy is then used to monitor the localization of the fluorescent protein as it hitches a ride through the cell. The subcellular localization of the fusion protein, if not immediately apparent, can then be determined by comparison to localizations generated by fluorescent protein fusions to known signalling sequences and proteins, or by direct comparison with fluorescent dyes. This review aims to be a tour guide for researchers wanting to travel this hitch-hiker's path, and for reviewers and readers who wish to understand their travel reports. It will describe some of the technology available for visualizing protein localizations, and some of the experimental approaches for optimizing and confirming localizations generated by particle bombardment in onion epidermal cells, the most commonly used experimental system. As the non-conservation of signal sequences in heterologous expression systems such as onion, and consequent mis-targeting of fusion proteins, is always a potential problem, the epidermal cells of the Argenteum mutant of pea are proposed as a model system.

Fractionating the neural correlates of individual working memory components underlying arithmetic problem solving skills in children.

PubMed

Metcalfe, Arron W S; Ashkenazi, Sarit; Rosenberg-Lee, Miriam; Menon, Vinod

2013-10-01

Baddeley and Hitch's multi-component working memory (WM) model has played an enduring and influential role in our understanding of cognitive abilities. Very little is known, however, about the neural basis of this multi-component WM model and the differential role each component plays in mediating arithmetic problem solving abilities in children. Here, we investigate the neural basis of the central executive (CE), phonological (PL) and visuo-spatial (VS) components of WM during a demanding mental arithmetic task in 7-9 year old children (N=74). The VS component was the strongest predictor of math ability in children and was associated with increased arithmetic complexity-related responses in left dorsolateral and right ventrolateral prefrontal cortices as well as bilateral intra-parietal sulcus and supramarginal gyrus in posterior parietal cortex. Critically, VS, CE and PL abilities were associated with largely distinct patterns of brain response. Overlap between VS and CE components was observed in left supramarginal gyrus and no overlap was observed between VS and PL components. Our findings point to a central role of visuo-spatial WM during arithmetic problem-solving in young grade-school children and highlight the usefulness of the multi-component Baddeley and Hitch WM model in fractionating the neural correlates of arithmetic problem solving during development. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Two-Store Model of Memory: Past Criticisms, Current Status, and Future Directions (Het Twee-Stadia Model van het Geheugen: Terugblik, Huidige Status en Toekomstige Ontwikkelingen)

DTIC Science & Technology

1990-06-01

levels -of- processing " ( Craik & Lockhart , 1972) en de "working memory" (Baddeley & Hitch, 1974) benaderingen deze verschijnselen beter...of storing information in LTS. 2.2 The levels -of- processing framework Craik and Lockhart (1972), in a very influential paper, proposed what they...Cognitive theory. (Vol. 1). (pp. 151-171). Hillsdale, N.J.: Erlbaum. Craik , F.l.M & Lockhart , R.S. (1972). Levels of processing : A frame- work

Ocean Drilling Program investigates hydrate ridge

NASA Astrophysics Data System (ADS)

Showstack, Randy

There are several ways to get onboard the JOIDES Resolution, a 143-meter long converted oil tanker that is a floating laboratory, and the pride of the Ocean Drilling Program (ODP). You can meet up with it at a port of call, or set down on its helicopter pad. Or you can hitch a ride by overnight supply boat, and then get lifted by crane to the Resolution by clinging to the outside of a rope transfer basket as this reporter did.

KSC-2009-3470

NASA Image and Video Library

2009-06-01

CAPE CANAVERAL, Fla. – Hitching a ride on the Shuttle Carrier Aircraft, or SCA, a modified Boeing 747, space shuttle Atlantis is ready for takeoff from El Paso. Atlantis landed at Edwards Air Force Base in California on May 24, which concluded mission STS-125, after two landing opportunities at Kennedy were waved off due to weather concerns. Atlantis is being returned to Florida on a ferry flight on the SCA. Atlantis' next assignment is the STS-129 mission, targeted to launch in November 2009. Photo credit: NASA/Ben Smegelsky

Rail and Motor Outloading Capability Study, Fort Chaffee, Arkansas,

DTIC Science & Technology

1978-11-01

instructors at Fort Eustis, Virginia, indicated that, to avoid wasted man - hours, there should be no more than eight men per crew, regardless of experience...level, total men per Man has to walk to front of vehicle as guide vehicle and to straighten bridge PL’s. Delays if all vehicles not at site at loading...vehicle (Storm, rain not included in total time) MILVAN married together 6-8 Some older cars have trailer hitches which Some 20-ft semis and man crew

Combat Squadrons of the Air Force, World War II,

DTIC Science & Technology

1982-01-01

1952. Inactivated on 1 Jul 1957. Redes- of a paddle wheel river boat, Air Force ignated 7o2d Troop Carrier Squadron blue, the windows lighted Air Force ...782d Bombard- hitched to a red wagon with wheels red, ment Squadron (Heavy) on 19 May hub yellow, tires and axles black, the 1943. Activated on 1 Aug...AD-A128 026 COMBAT SQUADRONS OF TOE AIR FORCE WORLD WAR IU) 1OFFICEOF AIR FORCE HISTORY WASHINGTON DC M MAURER UNCLASSIFIED F/G 15/7 NL

Gluteus Minimus and Gluteus Medius Muscle Activity During Common Rehabilitation Exercises in Healthy Postmenopausal Women.

PubMed

Ganderton, Charlotte; Pizzari, Tania; Cook, Jill; Semciw, Adam

2017-12-01

Study Design Controlled laboratory study, cross-sectional. Background The gluteus medius (GMed) and gluteus minimus (GMin) provide dynamic stability of the hip joint and pelvis. These muscles are susceptible to atrophy and injury in individuals during menopause, aging, and disease. Numerous studies have reported on the ability of exercises to elicit high levels of GMed activity; however, few studies have differentiated between the portions of the GMed, and none have examined the GMin. Objectives To quantify and rank the level of muscle activity of the 2 segments of the GMin (anterior and posterior fibers) and 3 segments of the GMed (anterior, middle, and posterior fibers) during 4 isometric and 3 dynamic exercises in a group of healthy, postmenopausal women. Methods Intramuscular electrodes were inserted into each segment of the GMed and GMin in 10 healthy, postmenopausal women. Participants completed 7 gluteal rehabilitation exercises, and average normalized muscle activity was used to rank the exercises from highest to lowest. Results The isometric standing hip hitch with contralateral hip swing was the highest-ranked exercise for all muscle segments except the anterior GMin, where it was ranked second. The highest-ranked dynamic exercise for all muscle segments was the dip test. Conclusion The hip hitch and its variations maximally activate the GMed and GMin muscle segments, and may be useful in hip muscle rehabilitation in postmenopausal women. J Orthop Sports Phys Ther 2017;47(12):914-922. Epub 15 Oct 2017. doi:10.2519/jospt.2017.7229.

Hitch-hiking parasitic wasp learns to exploit butterfly antiaphrodisiac

PubMed Central

Huigens, Martinus E.; Pashalidou, Foteini G.; Qian, Ming-Hui; Bukovinszky, Tibor; Smid, Hans M.; van Loon, Joop J. A.; Dicke, Marcel; Fatouros, Nina E.

2009-01-01

Many insects possess a sexual communication system that is vulnerable to chemical espionage by parasitic wasps. We recently discovered that a hitch-hiking (H) egg parasitoid exploits the antiaphrodisiac pheromone benzyl cyanide (BC) of the Large Cabbage White butterfly Pieris brassicae. This pheromone is passed from male butterflies to females during mating to render them less attractive to conspecific males. When the tiny parasitic wasp Trichogramma brassicae detects the antiaphrodisiac, it rides on a mated female butterfly to a host plant and then parasitizes her freshly laid eggs. The present study demonstrates that a closely related generalist wasp, Trichogramma evanescens, exploits BC in a similar way, but only after learning. Interestingly, the wasp learns to associate an H response to the odors of a mated female P. brassicae butterfly with reinforcement by parasitizing freshly laid butterfly eggs. Behavioral assays, before which we specifically inhibited long-term memory (LTM) formation with a translation inhibitor, reveal that the wasp has formed protein synthesis-dependent LTM at 24 h after learning. To our knowledge, the combination of associatively learning to exploit the sexual communication system of a host and the formation of protein synthesis-dependent LTM after a single learning event has not been documented before. We expect it to be widespread in nature, because it is highly adaptive in many species of egg parasitoids. Our finding of the exploitation of an antiaphrodisiac by multiple species of parasitic wasps suggests its use by Pieris butterflies to be under strong selective pressure. PMID:19139416

Hitch-hiking parasitic wasp learns to exploit butterfly antiaphrodisiac.

PubMed

Huigens, Martinus E; Pashalidou, Foteini G; Qian, Ming-Hui; Bukovinszky, Tibor; Smid, Hans M; van Loon, Joop J A; Dicke, Marcel; Fatouros, Nina E

2009-01-20

Many insects possess a sexual communication system that is vulnerable to chemical espionage by parasitic wasps. We recently discovered that a hitch-hiking (H) egg parasitoid exploits the antiaphrodisiac pheromone benzyl cyanide (BC) of the Large Cabbage White butterfly Pieris brassicae. This pheromone is passed from male butterflies to females during mating to render them less attractive to conspecific males. When the tiny parasitic wasp Trichogramma brassicae detects the antiaphrodisiac, it rides on a mated female butterfly to a host plant and then parasitizes her freshly laid eggs. The present study demonstrates that a closely related generalist wasp, Trichogramma evanescens, exploits BC in a similar way, but only after learning. Interestingly, the wasp learns to associate an H response to the odors of a mated female P. brassicae butterfly with reinforcement by parasitizing freshly laid butterfly eggs. Behavioral assays, before which we specifically inhibited long-term memory (LTM) formation with a translation inhibitor, reveal that the wasp has formed protein synthesis-dependent LTM at 24 h after learning. To our knowledge, the combination of associatively learning to exploit the sexual communication system of a host and the formation of protein synthesis-dependent LTM after a single learning event has not been documented before. We expect it to be widespread in nature, because it is highly adaptive in many species of egg parasitoids. Our finding of the exploitation of an antiaphrodisiac by multiple species of parasitic wasps suggests its use by Pieris butterflies to be under strong selective pressure.

The Structure of Working Memory in Young Children and Its Relation to Intelligence

PubMed Central

Gray, Shelley; Green, Samuel; Alt, Mary; Hogan, Tiffany P.; Kuo, Trudy; Brinkley, Shara; Cowan, Nelson

2016-01-01

This study investigated the structure of working memory in young school-age children by testing the fit of three competing theoretical models using a wide variety of tasks. The best fitting models were then used to assess the relationship between working memory and nonverbal measures of fluid reasoning (Gf) and visual processing (Gv) intelligence. One hundred sixty-eight English-speaking 7–9 year olds with typical development, from three states, participated. Results showed that Cowan’s three-factor embedded processes model fit the data slightly better than Baddeley and Hitch’s (1974) three-factor model (specified according to Baddeley, 1986) and decisively better than Baddeley’s (2000) four-factor model that included an episodic buffer. The focus of attention factor in Cowan’s model was a significant predictor of Gf and Gv. The results suggest that the focus of attention, rather than storage, drives the relationship between working memory, Gf, and Gv in young school-age children. Our results do not rule out the Baddeley and Hitch model, but they place constraints on both it and Cowan’s model. A common attentional component is needed for feature binding, running digit span, and visual short-term memory tasks; phonological storage is separate, as is a component of central executive processing involved in task manipulation. The results contribute to a zeitgeist in which working memory models are coming together on common ground (cf. Cowan, Saults, & Blume, 2014; Hu, Allen, Baddeley, & Hitch, 2016). PMID:27990060

Development and Evaluation of a Remedial Reading Workbook for Navy Training.

DTIC Science & Technology

1979-12-01

quirements (1973) and the Bluejackets’ Manual, 20th Edition (1978). The workbook is based on established remedial reading principles and many of the exercises...knot is just a little over one mile an hour; or a knot in a rope; hitches and bends in a line LASH To tie up with a line (or wire). Le , inq is what you...long i. (Exercise 5 - silent vowel is circled) 1 - saior, 2 b* 3 - peoce, 4 - rescul 5 - ste_, 6 - fantag 7 - inbc&d, 8 - issu, 9 - le , 10 - rel e, 11

Key Considerations for Irregular Security Forces in Counterinsurgency

DTIC Science & Technology

2011-06-10

wounded and one slightly. It was decided to move to virgin ground two miles away. The other moves went without a hitch and both Firqats and civilians...using the area for years as a sort of holiday camp for rest and recuperation.‖ 121Sibley, 304. 122Akehurst, 75. ―New positions were established at...Regiment and called ―Hammer.‖ It was almost due north of Raysut and a major blow to the enemy who had been using the area for years as a sort of holiday

KSC-2009-3469

NASA Image and Video Library

2009-06-01

CAPE CANAVERAL, Fla. – Hitching a ride on the Shuttle Carrier Aircraft, or SCA, a modified Boeing 747, space shuttle Atlantis has arrived at Biggs Armuy Air Field in El Paso, Texas. Atlantis landed at Edwards Air Force Base in California on May 24, which concluded mission STS-125, after two landing opportunities at Kennedy were waved off due to weather concerns. Atlantis is being returned to Florida on a ferry flight on the SCA. Atlantis' next assignment is the STS-129 mission, targeted to launch in November 2009. Photo credit: NASA/Ben Smegelsky

Similar Modes of Interaction Enable Trailer Hitch and EDC3 To Associate with DCP1 and Me31B in Distinct Protein Complexes▿ †

PubMed Central

Tritschler, Felix; Eulalio, Ana; Helms, Sigrun; Schmidt, Steffen; Coles, Murray; Weichenrieder, Oliver; Izaurralde, Elisa; Truffault, Vincent

2008-01-01

Trailer Hitch (Tral or LSm15) and enhancer of decapping-3 (EDC3 or LSm16) are conserved eukaryotic members of the (L)Sm (Sm and Like-Sm) protein family. They have a similar domain organization, characterized by an N-terminal LSm domain and a central FDF motif; however, in Tral, the FDF motif is flanked by regions rich in charged residues, whereas in EDC3 the FDF motif is followed by a YjeF_N domain. We show that in Drosophila cells, Tral and EDC3 specifically interact with the decapping activator DCP1 and the DEAD-box helicase Me31B. Nevertheless, only Tral associates with the translational repressor CUP, whereas EDC3 associates with the decapping enzyme DCP2. Like EDC3, Tral interacts with DCP1 and localizes to mRNA processing bodies (P bodies) via the LSm domain. This domain remains monomeric in solution and adopts a divergent Sm fold that lacks the characteristic N-terminal α-helix, as determined by nuclear magnetic resonance analyses. Mutational analysis revealed that the structural integrity of the LSm domain is required for Tral both to interact with DCP1 and CUP and to localize to P-bodies. Furthermore, both Tral and EDC3 interact with the C-terminal RecA-like domain of Me31B through their FDF motifs. Together with previous studies, our results show that Tral and EDC3 are structurally related and use a similar mode to associate with common partners in distinct protein complexes. PMID:18765641

Similar modes of interaction enable Trailer Hitch and EDC3 to associate with DCP1 and Me31B in distinct protein complexes.

PubMed

Tritschler, Felix; Eulalio, Ana; Helms, Sigrun; Schmidt, Steffen; Coles, Murray; Weichenrieder, Oliver; Izaurralde, Elisa; Truffault, Vincent

2008-11-01

Trailer Hitch (Tral or LSm15) and enhancer of decapping-3 (EDC3 or LSm16) are conserved eukaryotic members of the (L)Sm (Sm and Like-Sm) protein family. They have a similar domain organization, characterized by an N-terminal LSm domain and a central FDF motif; however, in Tral, the FDF motif is flanked by regions rich in charged residues, whereas in EDC3 the FDF motif is followed by a YjeF_N domain. We show that in Drosophila cells, Tral and EDC3 specifically interact with the decapping activator DCP1 and the DEAD-box helicase Me31B. Nevertheless, only Tral associates with the translational repressor CUP, whereas EDC3 associates with the decapping enzyme DCP2. Like EDC3, Tral interacts with DCP1 and localizes to mRNA processing bodies (P bodies) via the LSm domain. This domain remains monomeric in solution and adopts a divergent Sm fold that lacks the characteristic N-terminal alpha-helix, as determined by nuclear magnetic resonance analyses. Mutational analysis revealed that the structural integrity of the LSm domain is required for Tral both to interact with DCP1 and CUP and to localize to P-bodies. Furthermore, both Tral and EDC3 interact with the C-terminal RecA-like domain of Me31B through their FDF motifs. Together with previous studies, our results show that Tral and EDC3 are structurally related and use a similar mode to associate with common partners in distinct protein complexes.

Cryogenic Heat Pipe Experiment (CRYOHP)

NASA Technical Reports Server (NTRS)

Mcintosh, Roy

1992-01-01

The objective of the CRYOHP experiment is to conduct a shuttle experiment that demonstrates the reliable operation of two oxygen heat pipes in microgravity. The experiment will perform the following tasks: (1) demonstrate startup of the pipes from the supercritical state; (2) measure the heat transport capacity of the pipes; (3) measure evaporator and condenser film coefficients; and (4) work shuttle safety issues. The approach for the experiment is as follows: (1) fly two axially grooved oxygen heat pipes attached to mechanical stirling cycle tactical coolers; (2) integrate experiment in hitch-hiker canister; and (3) fly on shuttle and control from ground.

Robotic Materials Handling in Space: Mechanical Design of the Robot Operated Materials Processing System HitchHiker Experiment

NASA Technical Reports Server (NTRS)

Voellmer, George

1997-01-01

The Goddard Space Flight Center has developed the Robot Operated Materials Processing System (ROMPS) that flew aboard STS-64 in September, 1994. The ROMPS robot transported pallets containing wafers of different materials from their storage racks to a furnace for thermal processing. A system of tapered guides and compliant springs was designed to deal with the potential misalignments. The robot and all the sample pallets were locked down for launch and landing. The design of the passive lockdown system, and the interplay between it and the alignment system are presented.

The Space Shuttle Discovery hitched a ride on a special 747 carrier aircraft for the flight from California to the Kennedy Space Center, FL, on August 19, 2005

NASA Image and Video Library

2005-08-19

The Space Shuttle Discovery hitched a ride on NASA's modified Boeing 747 Shuttle Carrier Aircraft for the flight from the Dryden Flight Research Center in California, to Kennedy Space Center, Florida, on August 19, 2005. The cross-country ferry flight to return Discovery to Florida after it's landing in California will take two days, with stops at several intermediate points for refueling. Space Shuttle Discovery landed safely at NASA's Dryden Flight Research Center at Edwards Air Force Base in California at 5:11:22 a.m. PDT, August 9, 2005, following the very successful 14-day STS-114 return to flight mission. During their two weeks in space, Commander Eileen Collins and her six crewmates tested out new safety procedures and delivered supplies and equipment the International Space Station. Discovery spent two weeks in space, where the crew demonstrated new methods to inspect and repair the Shuttle in orbit. The crew also delivered supplies, outfitted and performed maintenance on the International Space Station. A number of these tasks were conducted during three spacewalks. In an unprecedented event, spacewalkers were called upon to remove protruding gap fillers from the heat shield on Discovery's underbelly. In other spacewalk activities, astronauts installed an external platform onto the Station's Quest Airlock and replaced one of the orbital outpost's Control Moment Gyroscopes. Inside the Station, the STS-114 crew conducted joint operations with the Expedition 11 crew. They unloaded fresh supplies from the Shuttle and the Raffaello Multi-Purpose Logistics Module. Before Discovery undocked, the crews filled Raffeallo with unneeded items and returned to Shuttle payload bay. Discovery launched on July 26 and spent almost 14 days on orbit.

Water-Quality and Fish-Community Data for the Niobrara National Scenic River, Nebraska, 2003-05

USGS Publications Warehouse

Dietsch, Benjamin

2008-01-01

In 1991, a 76-mile reach of the Niobrara River in north-central Nebraska was designated as a National Scenic River (NSR). This reach of the river hosts a unique ecosystem that provides habitat for a diverse fish and wildlife population that include several threatened and endangered species. The Niobrara NSR also is a popular destination for campers, canoeists, kayakers, and tubers. Changes in surface-water quality, related to recreation, industrial and municipal discharge, and agricultural activities in the region have the potential to affect fish and wildlife populations within the Niobrara NSR. Additionally, water users may be at risk if elevated concentrations of chemical or biological contaminants are present in the waterway. The U.S. Geological Survey (USGS) and the National Park Service (NPS) began a 3-year cooperative study of water-quality characteristics in Niobrara NSR in 2003. During the study, water samples were collected for analysis of a suite of physical, chemical, and biological indicators of water quality in the Niobrara River. The resulting data have been published previously (Hitch and others, 2004; Hitch and others, 2005) and included: major ions, nutrients, trace elements, pesticides, organic (wastewater) compounds, bacteria, and suspended sediment. In addition to water-quality sampling, fish communities were sampled to identify the presence and diversity of species at selected sites (data available online in Annual Water Data Reports). These water-quality and fish-community data are summarized in this report. The data were collected to provide baseline information that will help NPS managers determine if changes in recreational activities, land-use practices, and other factors are affecting the Niobrara River.

Comparing the tensile strength of square and reversing half-hitch alternating post knots

PubMed Central

Wu, Vincent; Sykes, Edward A.; Mercer, Dale; Hopman, Wilma M.; Tang, Ephraim

2017-01-01

Background Square knots are the gold standard in hand-tie wound closure, but are difficult to reproduce in deep cavities, inadvertently resulting in slipknots. The reversing half-hitch alternating post (RHAP) knot has been suggested as an alternative owing to its nonslip nature and reproducibility in limited spaces. We explored whether the RHAP knot is noninferior to the square knot by assessing tensile strength. Methods We conducted 10 trials for each baseline and knot configuration, using 3–0 silk and 3–0 polyglactin 910 sutures. We compared tensile strength between knot configurations at the point of knot failure between slippage and breakage. Results Maximal failure strength (mean ± SD) in square knots was reached with 4-throw in both silk (30 ± 1.5 N) and polyglactin 910 (39 ± 12 N). For RHAP knots, maximal failure strength was reached at 5-throw for both silk (31 ± 1.5 N) and polyglactin 910 (41 ± 13 N). In both sutures, there were no strength differences between 3-throw square and 4-throw RHAP, between 4-throw square and 5-throw RHAP, or between 5-throw square and 6-throw RHAP knots. Polyglactin 910 sutures, in all knot configurations, were more prone to slippage than silk sutures (p < 0.001). Conclusion The difference in mean tensile strength could be attributed to the proportion of knot slippage versus breakage, which is material-dependent. Future studies can re-evaluate findings in monofilament sutures and objectively assess the reproducibility of square and RHAP knots in deep cavities. Our results indicate that RHAP knots composed of 1 extra throw provide equivalent strength to square knots and may be an alternative when performing hand-ties in limited cavities with either silk or polyglactin 910 sutures. PMID:28327276

Comparing the tensile strength of square and reversing half-hitch alternating post knots.

PubMed

Wu, Vincent; Sykes, Edward A; Mercer, Dale; Hopman, Wilma M; Tang, Ephraim

2017-06-01

Square knots are the gold standard in hand-tie wound closure, but are difficult to reproduce in deep cavities, inadvertently resulting in slipknots. The reversing half-hitch alternating post (RHAP) knot has been suggested as an alternative owing to its nonslip nature and reproducibility in limited spaces. We explored whether the RHAP knot is noninferior to the square knot by assessing tensile strength. We conducted 10 trials for each baseline and knot configuration, using 3-0 silk and 3-0 polyglactin 910 sutures. We compared tensile strength between knot configurations at the point of knot failure between slippage and breakage. Maximal failure strength (mean ± SD) in square knots was reached with 4-throw in both silk (30 ± 1.5 N) and polyglactin 910 (39 ± 12 N). For RHAP knots, maximal failure strength was reached at 5-throw for both silk (31 ± 1.5 N) and polyglactin 910 (41 ± 13 N). In both sutures, there were no strength differences between 3-throw square and 4-throw RHAP, between 4-throw square and 5-throw RHAP, or between 5-throw square and 6-throw RHAP knots. Polyglactin 910 sutures, in all knot configurations, were more prone to slippage than silk sutures ( p < 0.001). The difference in mean tensile strength could be attributed to the proportion of knot slippage versus breakage, which is material-dependent. Future studies can re-evaluate findings in monofilament sutures and objectively assess the reproducibility of square and RHAP knots in deep cavities. Our results indicate that RHAP knots composed of 1 extra throw provide equivalent strength to square knots and may be an alternative when performing hand-ties in limited cavities with either silk or polyglactin 910 sutures.

Do viruses use vectors to penetrate mucus barriers?

PubMed Central

Ribbeck, Katharina

2010-01-01

I propose a mechanism by which viruses successfully infect new individuals, despite being immotile particles with no ability for directed movement. Within cells, viral particle movements are directed by motors and elements of the cytoskeleton, but how viruses cross extracellular barriers, like mucus, remains a mystery. I propose that viruses cross these barriers by hitch-hiking on bacteria or sperm cells which can transport themselves across mucosal layers designed to protect the underlying cells from pathogen attack. An important implication of this hypothesis is that agents that block interactions between viruses and bacteria or sperm may be new tools for disease prevention. PMID:20190864

The global transport of dust: An intercontinental river of dust, microorganisms and toxic chemicals flows through the Earth's atmosphere

USGS Publications Warehouse

Griffin, Dale; Kellogg, Christina; Garrison, Virginia; Shinn, Eugene

2002-01-01

The coral reefs in the Caribbean have been deteriorating since the 1970s, and no one is quite sure why. Such environmental devastation is usually blamed on Homo sapiens, but that doesn’t seem to be what’s going on here. Recently, some scientists at the USGS think they’ve solved the puzzle: Bacteria and fungi have been hitching trans-Atlantic rides on dust from the Sahara desert and settling into the warm waters of the Caribbean. Microbiologist Dale Griffin and his colleagues make the case for this hypothesis and explore the dangers of dust and microbe transport across the globe.

A lateral tarsorrhaphy with forehead hitch to pre-empt and treat burns ectropion with a contextual review of burns ectropion management

PubMed Central

Lymperopoulos, Nikolaos S; Jordan, Daniel J; Jeevan, Ranjeet; Shokrollahi, Kayvan

2016-01-01

Introduction: Facial burns around the eyes and eyelid ectropion can lead to corneal exposure, irritation, dryness, epiphora, infection or visual loss. We undertook a review of the published articles describing management of eyelid burns as well as methods to treat or prevent ectropion. We describe early experience of a surgical technique that we have found to mitigate ectropion in facial burns with peri-ocular involvement. Materials and methods: Two illustrative cases with our surgical technique is described from our experience of three cases. We reviewed the literature using the PubMed and EMBASE databases using the search terms ‘burn’ and ‘ectropion’. Results: The literature review produced a total of 17 relevant papers. Treatment options for eyelid burns were varied and were invariably level 4 or 5 evidence. Various techniques were used to treat eyelid burns including the use of a full thickness skin graft with or without concurrent scar contracture release but also use of a local flap reconstruction with or without a tissue expander or release of the underlying muscle. Other techniques included canthoplasty, Z-plasty, forehead flaps, fat transfer, and tarsorrhaphy with full thickness skin grafting. In general, the focus of articles was therapeutic and reconstructive rather than pre-emptive/preventative management. Procedure: We describe our early experience of a novel technique for temporary lateral tarsorrhaphy with forehead hitch which protexts the globe and counters the scar- and gravity-related ectropic effects on the lower eyelids. Discussion: Facial burns pose a difficult problem to the burn surgeon, especially when the eyelids are affected, both directly or indirectly. The optimal surgical management of eyelid burns remains unclear and the literature base lies mainly in the domain of case series. We review the literature on this subject and tabulate our findings and also describe our contribution to this area with a method of lateral and lower lid elevator that we have found valuable. PMID:29799558

Biorobotic adhesion in water using suction cups.

PubMed

Bandyopadhyay, Promode R; Hrubes, J Dana; Leinhos, Henry A

2008-03-01

Echeneid fish, limpets and octopi use suction cups for underwater adhesion. When echeneid fish use suckers to 'hitch a ride' on sharks (which have riblet-patterned skins), the apparent absence of any pump or plumbing may be an advantage over biorobotic suction cups. An intriguing question is: How do they achieve seemingly persistent leak-free contact at low energy cost over rough surfaces? The design features of their suckers are explored in a biorobotic context of adhesion in water over rough surfaces. We have carried out experiments to compare the release force and tenacity of man-made suction cups with those reported for limpets and echeneid fish. Applied tensile and shear release forces were monotonically increased until release. The effects of cup size and type, host surface roughness, curvature and liquid surface tension have been examined. The flow of water in the sharkskin-like host surface roughness has been characterized. The average tenacity is 5.28 N cm(-2) (sigma = 0.53 N cm(-2), N = 37) in the sub-ambient pressure range of 14.6-49.0 kPa, in man-made cups for monotonically increasing applied release force. The tenacity is lower for harmonically oscillating release forces. The dynamic structural interactions between the suction cup and the oscillating applied forcing are discussed. Inspired by the matching of sharkskin riblet topology in echeneid fish suckers, it was found that biorobotic sealed contact over rough surfaces is also feasible when the suction cup makes a negative copy of the rough host surface. However, for protracted, persistent contact, the negative topology would have to be maintained by active means. Energy has to be spent to maintain the negative host roughness topology to minute detail, and protracted hitch-riding on sharks for feeding may not be free for echeneid fish. Further work is needed on the mechanism and efficiency of the densely populated tiny actuators in the fish suckers that maintain leak-proof contact with minimal energy cost and the feasibility of their biorobotic replication.

A lateral tarsorrhaphy with forehead hitch to pre-empt and treat burns ectropion with a contextual review of burns ectropion management.

PubMed

Lymperopoulos, Nikolaos S; Jordan, Daniel J; Jeevan, Ranjeet; Shokrollahi, Kayvan

2016-01-01

Facial burns around the eyes and eyelid ectropion can lead to corneal exposure, irritation, dryness, epiphora, infection or visual loss. We undertook a review of the published articles describing management of eyelid burns as well as methods to treat or prevent ectropion. We describe early experience of a surgical technique that we have found to mitigate ectropion in facial burns with peri-ocular involvement. Two illustrative cases with our surgical technique is described from our experience of three cases. We reviewed the literature using the PubMed and EMBASE databases using the search terms 'burn' and 'ectropion'. The literature review produced a total of 17 relevant papers. Treatment options for eyelid burns were varied and were invariably level 4 or 5 evidence. Various techniques were used to treat eyelid burns including the use of a full thickness skin graft with or without concurrent scar contracture release but also use of a local flap reconstruction with or without a tissue expander or release of the underlying muscle. Other techniques included canthoplasty, Z-plasty, forehead flaps, fat transfer, and tarsorrhaphy with full thickness skin grafting. In general, the focus of articles was therapeutic and reconstructive rather than pre-emptive/preventative management. We describe our early experience of a novel technique for temporary lateral tarsorrhaphy with forehead hitch which protexts the globe and counters the scar- and gravity-related ectropic effects on the lower eyelids. Facial burns pose a difficult problem to the burn surgeon, especially when the eyelids are affected, both directly or indirectly. The optimal surgical management of eyelid burns remains unclear and the literature base lies mainly in the domain of case series. We review the literature on this subject and tabulate our findings and also describe our contribution to this area with a method of lateral and lower lid elevator that we have found valuable.

Measuring spatial variability in soil characteristics

DOEpatents

Hoskinson, Reed L.; Svoboda, John M.; Sawyer, J. Wayne; Hess, John R.; Hess, J. Richard

2002-01-01

The present invention provides systems and methods for measuring a load force associated with pulling a farm implement through soil that is used to generate a spatially variable map that represents the spatial variability of the physical characteristics of the soil. An instrumented hitch pin configured to measure a load force is provided that measures the load force generated by a farm implement when the farm implement is connected with a tractor and pulled through or across soil. Each time a load force is measured, a global positioning system identifies the location of the measurement. This data is stored and analyzed to generate a spatially variable map of the soil. This map is representative of the physical characteristics of the soil, which are inferred from the magnitude of the load force.

NASA Tech Briefs, August 2007

NASA Technical Reports Server (NTRS)

2007-01-01

Topics include: Program Merges SAR Data on Terrain and Vegetation Heights; Using G(exp 4)FETs as a Data Router for In-Plane Crossing of Signal Paths; Two Algorithms for Processing Electronic Nose Data; Radiation-Tolerant Dual Data Bus; General-Purpose Front End for Real-Time Data Processing; Nanocomposite Photoelectrochemical Cells; Ultracapacitor-Powered Cordless Drill, Cumulative Timers for Microprocessors; Photocatalytic/Magnetic Composite Particles; Separation and Sealing of a Sample Container Using Brazing; Automated Aerial Refueling Hitches a Ride on AFF; Cobra Probes Containing Replaceable Thermocouples; High-Speed Noninvasive Eye-Tracking System; Detergent-Specific Membrane Protein Crystallization Screens; Evaporation-Cooled Protective Suits for Firefighters; Plasmonic Antenna Coupling for QWIPs; Electronic Tongue Containing Redox and Conductivity Sensors; Improved Heat-Stress Algorithm; A Method of Partly Automated Testing of Software; Rover Wheel-Actuated Tool Interface; and Second-Generation Electronic Nose.

Visual distraction and visuo-spatial memory: a sandwich effect.

PubMed

Tremblay, Sébastien; Nicholls, Alastair P; Parmentier, Fabrice B R; Jones, Dylan M

2005-01-01

The functional characteristics of visuo-spatial serial memory and its sensitivity to irrelevant visual information are examined in the present study, through the investigation of the sandwich effect (e.g., Hitch, 1975). The memory task was one of serial recall for the position of a sequence of seven spatially and temporally separated dots. The presence of irrelevant dots interpolated with to-be-remembered dots affected performance over most serial positions (Experiment 1) but that effect was significantly reduced when the interpolated dots were distinct from the to-be-remembered dots by colour and shape (Experiment 2). Parallels are made between verbal and spatial serial memory, and the reduction of the sandwich effect is discussed in terms of the contribution of perceptual organisation and attentional factors in short-term memory.

Heavy metal tolerance in plants: A model evolutionary system.

PubMed

Macnair, M R

1987-12-01

Evolved tolerance to toxic concentrations of heavy metals in plants inhabiting spoil heaps of mines is a well known phenomenon that has been the subject of much research in the last two decades. These plants are useful models for studying processes involved in the early stages of the speciation of edaphic endemics. Recent work has revealed the importance of several phenomena in the differentiation of tolerant populations, including natural selection, founder effects and 'hitch-hiking', and has demonstrated the early evolution of morphological differentiation and reproductive isolating mechanisms. Further studies of the biochemistry and molecular biology of heavy metal tolerance will help to show why some plant groups, such as Agrostis, are far more prone to evolve tolerance than others. Copyright © 1987. Published by Elsevier Ltd.

[Use of the Omega plate for stabilisation of acetabular fractures: first experience].

PubMed

Šrám, J; Taller, S; Lukáš, R; Endrych, L

2013-01-01

The aim of our study is to solve the problem of insufficient fixation of comminuted fractures of the quadrilateral plane and the iliopectineal line. These fixation problems occur while using the standard narrow 3.5 mm fixation plate applied from a modified Stoppa approach. A new plate developed by the authors--the Omega plate--fulfils the requirements. In the period 2010-2012, we performed 156 stabilisations of pelvic ring fractures and acetabular fractures. We used the modified Stoppa approach applying the standard fixation plate in 24 patients and the Omega plate in 15 patients. The patient group with the Omega plate included 10 male and five female patients with the average age of 61 years (range, 30-72). Only 11 patients were followed up, with an average period of 13.3 months, because one patient was lost to followup and three patients were shortly after surgery. The surgical technique of Omega plate application is described in detail. The clinical evaluation of post-operative results was based on the Harris Hip Score; the graphical results were rated using the Matta and Pohlemann criteria. The Stoppa approach alone was used in four patients, combination of two approaches (Stoppa and Kocher-Langenbeck approach) was used in six cases and three approaches were employed in five patients. No adverse intra- or post-operative events were recorded. Excellent or satisfactory graphical results were obtained in 12 patients and an unsatisfactory graphical outcome was recorded in three cases. In the follow-up period ranging from 8 to 22 months, 11 patients healed. Late complications included avascular femoral head necrosis in two and severe post-traumatic coxarthrosis in three patients. Due to these complications, all five patients underwent total hip arthroplasty without previous Omega plate removal at an average interval of 15 months from the primary pelvic surgery. They were not included in the follow-up evaluation. The remaining six patients had an average Harris Hip Score of 88 points (range, 81-98). The novel plate, shaped as a reverse omega letter, enables fixation of the quadrilateral area of the acetabulum through pressure of the arc of the plate against this area. Hitches, with holes for screw insertion, attached to the Omega plate in its middle part allow for fixation of fragments above the linea arcuata simply by pressure. Hitches in the ventral part provide for plate fixation to the ventral acetabular column and the superior pubic ramus. Hitches in the posterior segment of the plate facilitate insertion of a long screw in the posterior acetabular column from an additional iliac approach for stabilisation of simple acetabular fractures. The Omega plates are manufactured in several modifications. The Omega plate enables us to fix fractures of the superior pubic ramus, fractures of the anterior acetabular column, fractures of the quadrilateral acetabular plate, fractures in the iliopectineal line and simple fractures of the posterior column. A CT-defined projection of the pelvic inlet based on pre-operative CT scans allows us to choose the appropriate plate size and to shape the plate pre-operatively. After a technically well performed Stoppa approach and good fragment reduction, the application of an Omega plate is easy if our recommendations are followed. Fixation of all fragments of the anterior column and the quadrilateral plate is very stable and the Omega plate is highly resistant to secondary loss of reduction. A potential total hip arthroplasty does not require Omega plate removal.

A Hitch-hiker's Guide to Stochastic Differential Equations. Solution Methods for Energetic Particle Transport in Space Physics and Astrophysics

NASA Astrophysics Data System (ADS)

Strauss, R. Du Toit; Effenberger, Frederic

2017-10-01

In this review, an overview of the recent history of stochastic differential equations (SDEs) in application to particle transport problems in space physics and astrophysics is given. The aim is to present a helpful working guide to the literature and at the same time introduce key principles of the SDE approach via "toy models". Using these examples, we hope to provide an easy way for newcomers to the field to use such methods in their own research. Aspects covered are the solar modulation of cosmic rays, diffusive shock acceleration, galactic cosmic ray propagation and solar energetic particle transport. We believe that the SDE method, due to its simplicity and computational efficiency on modern computer architectures, will be of significant relevance in energetic particle studies in the years to come.

Case report: prenatal diagnosis of diastrophic dysplasia by ultrasound at 21 weeks of gestation in a mother with massive obesity.

PubMed

Jung, C; Sohn, C; Sergi, C

1998-04-01

Routine prenatal ultrasound of a massively obese mother at 21 weeks of gestation revealed short-limb dwarfism in the fetus. The proportionate shortening of tubular bones of about 50 per cent of the normal length, the absence of thoracic dysplasia, and a normal head circumference narrowed the diagnosis down to a severe but non-lethal skeletal dysplasia. Ulnar deviation of the hands and talipes made diastrophic dysplasia the most likely differential diagnosis. At post-mortem clinical examination, the diagnosis of diastrophic dysplasia was clearly apparent due to highly specific 'hitch-hiker thumbs', similarly luxated big toes, facial dysmorphism, and a cleft palate. Retrospective re-evaluation of the prenatal ultrasound videos revealed the misplaced thumbs, which together with the ulnar deviation of the wrist and suspected talipes, led to the conclusion that the definitive diagnosis can be established prenatally, even in a mother with massive obesity.

Material efficiency: rare and critical metals.

PubMed

Ayres, Robert U; Peiró, Laura Talens

2013-03-13

In the last few decades, progress in electronics, especially, has resulted in important new uses for a number of geologically rare metals, some of which were mere curiosities in the past. Most of them are not mined for their own sake (gold, the platinum group metals and the rare Earth elements are exceptions) but are found mainly in the ores of the major industrial metals, such as aluminium, copper, zinc and nickel. We call these major metals 'attractors' and the rare accompanying metals 'hitch-hikers'. The key implication is that rising prices do not necessarily call forth greater output because that would normally require greater output of the attractor metal. We trace the geological relationships and the functional uses of these metals. Some of these metals appear to be irreplaceable in the sense that there are no known substitutes for them in their current functional uses. Recycling is going to be increasingly important, notwithstanding a number of barriers.

Center Innovation Fund: JSC CIF Characterize Human Forward Contamination

NASA Technical Reports Server (NTRS)

Rucker, Michelle A.

2017-01-01

Let's face it: wherever we go, we will inevitably carry along the little critters that live in and on us. Conventional wisdom has long held that it's unlikely those critters could survive the space environment, but in 2007 microscopic animals called Tardigrades survived exposure to space and in 2008 Cyanobacteria lived for 548 days outside the International Space Station (ISS). But what about the organisms we might reasonably expect a crewed spacecraft to leak or vent? Do we even know what they are? How long might our tiny hitch-hikers survive in close proximity to a warm spacecraft that periodically leaks/vents water or oxygen-and how might they mutate with long-duration exposure? Unlike the Mars rovers that we cleaned once and sent on their way, crew members will provide a constantly regenerating contaminant source. Are we prepared to certify that we can meet forward contamination protocols as we search for life at new destinations?

Hydronephrosis: Comparison of extrinsic vessel versus intrinsic ureteropelvic junction obstruction groups and a plea against the vascular hitch procedure.

PubMed

Menon, Prema; Rao, Katragadda L N; Sodhi, Kushaljit S; Bhattacharya, A; Saxena, Akshay K; Mittal, Bhagwant R

2015-04-01

Pediatric ureteropelvic junction obstruction (UPJO) due to an extrinsic crossing vessel (CV) is rare and often remains undiagnosed preoperatively. Vascular hitch procedures are often performed as associated intrinsic obstruction is not expected. We compared data and intravenous urography (IVU) findings of patients with aberrant CV versus those with intrinsic UPJO, all undergoing open dismembered pyeloplasty. Is accurate pre-operative diagnosis of aberrant CV causing extrinsic UPJO possible? To assess differences in the demographic, clinical, radiological, intra-operative features and postoperative improvement after pyeloplasty between patients with a CV and those with only intrinsic UPJO. Prospective study of all children below 12 years with UPJO presenting to a tertiary referral centre and who underwent open Anderson - Hynes dismembered pyeloplasty between 2003 and 2013 was conducted. Pre-operative investigations included serial ultrasonography, renal dynamic [ethylene di-cysteine (EC)] scan and IVU. These were repeated 3 months after pyeloplasty. Pre-operative IVUs of children with CV were compared with the IVUs of an equal number of similar aged children, randomly selected from the intrinsic obstruction group. Pyeloplasty was performed in 643 children during the study period. Data of 33 children with aberrant CVs (mean age 6.99 years) were compared with the remaining 610 children (mean age 3.27 years) with only intrinsic obstruction. Highly significant associations of those with CV included age above 2 years, female gender, associated anomalies, abdominal pain in those above 2 years and poor preoperative function on IVU. Specific IVU features which were statistically highly significant in favor of presence of CV were small, intrarenal and globular flat bottomed pelvis. (Figure) Calyceal dilatation was also more prominent in the CV group. A funnel shaped, extrarenal pelvis was highly significant in favor of intrinsic obstruction. There was associated intrinsic obstruction in addition to CV obstruction in 8 children. All children symptomatically improved after pyeloplasty and did well on long term follow up. The majority showed improvement or stabilization of function on EC scan. With the advent of antenatal ultrasonography, most children with UPJO are detected early. Children with CV tend to present later. This is often detected during surgery. Color Doppler is useful but is operator dependant and not performed routinely. In this study, IVU showed the presence of obstruction and loss of function unlike color Doppler, but also revealed specific diagnostic features not previously reported in literature. This can help in accurate preoperative prediction and avoid endopyelotomy, or a dorsal lumbotomy/retroperitoneal approach. Renal function in CVs is expected to be good as the obstruction is thought to be intermittent. However, we noted delayed contrast uptake on IVU in 60.6% and differential renal function on EC scan below 40% in 17 patients (56.6%). These indicate the effect of the obstruction on the renal parenchyma and the importance of early detection. Higher association with other anomalies and higher incidence in females has also not been emphasized in the literature so far. We noted associated intrinsic obstruction in 24.24% patients which is highly significant. This category of patients is likely to be missed and inappropriately treated if a "vascular hitch procedure" is performed. None of our patients had postoperative complications. Characteristic features were seen on IVU helping in preoperative diagnosis which can be extrapolated to magnetic resonance urography. There is a higher association of CV in age above 2 years, females, associated congenital anomalies, delayed uptake on IVU and differential renal function below 40% compared to intrinsic obstruction. Associated intrinsic obstruction in 24% with no postoperative complications indicates the superiority of dismembered pyeloplasty over vasculopexy procedures. Copyright © 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Bed bug aggregation on dirty laundry: a mechanism for passive dispersal.

PubMed

Hentley, William T; Webster, Ben; Evison, Sophie E F; Siva-Jothy, Michael T

2017-09-28

Bed bugs have shown a recent and rapid global expansion that has been suggested to be caused by cheap air travel. How a small, flightless and anachoretic insect that hides within its host's sleeping area manages to travel long distances is not yet clear. Bed bugs are attracted to the odour of sleeping humans and we suggest that soiled clothing may present a similarly attractive cue, allowing bed bugs to 'hitch-hike' around the world after aggregating in the laundry bags of travellers. We show that (1) soiled clothing is significantly more attractive than clean clothing to active bed bugs moving within a bedroom sized arena and (2) elevation of CO 2 to a level that simulates human occupancy in the same arena appears to initiate search behaviour rather than direct it. Our results show, for the first time, how leaving worn clothing exposed in sleeping areas when travelling can be exploited by bed bugs to facilitate passive dispersal.

ME31B globally represses maternal mRNAs by two distinct mechanisms during the Drosophila maternal-to-zygotic transition.

PubMed

Wang, Miranda; Ly, Michael; Lugowski, Andrew; Laver, John D; Lipshitz, Howard D; Smibert, Craig A; Rissland, Olivia S

2017-09-06

In animal embryos, control of development is passed from exclusively maternal gene products to those encoded by the embryonic genome in a process referred to as the maternal-to-zygotic transition (MZT). We show that the RNA-binding protein, ME31B, binds to and represses the expression of thousands of maternal mRNAs during the Drosophila MZT. However, ME31B carries out repression in different ways during different phases of the MZT. Early, it represses translation while, later, its binding leads to mRNA destruction, most likely as a consequence of translational repression in the context of robust mRNA decay. In a process dependent on the PNG kinase, levels of ME31B and its partners, Cup and Trailer Hitch (TRAL), decrease by over 10-fold during the MZT, leading to a change in the composition of mRNA-protein complexes. We propose that ME31B is a global repressor whose regulatory impact changes based on its biological context.

Working memory as separable subsystems: a study with Portuguese primary school children.

PubMed

Campos, Isabel S; Almeida, Leandro S; Ferreira, Aristides I; Martinez, Luis F

2013-01-01

Although much research has been done to study the working memory structure in children in their first school years, the relation of cognitive constructs involved in this process remains uncertain. In particular, it is unclear whether working memory is a domain general construct that coordinates separate codes of verbal and visuospatial storage or whether it is a domain-specific construct with distinct resources of verbal and visuospatial information. This paper investigates the structure of working memory, by using the Working Memory Test Battery for Children (WMTB-C) and by doing confirmatory factor analyses (CFAs) on a sample of Portuguese children (n = 103) between 8 and 9 years of age. The results of the confirmatory factor analyses that provide the best fit of the data correspond to the model that includes Central Executive and Visuospatial Sketchpad in the same factor, co-varying with a Phonological Loop factor. Moreover, the traditional working memory tripartite structure--based on the Baddeley and Hitch Model--revealed good fit to the data.

Impaired verbal short-term memory in Down syndrome reflects a capacity limitation rather than atypically rapid forgetting.

PubMed

M Purser, Harry R; Jarrold, Christopher

2005-05-01

Individuals with Down syndrome suffer from relatively poor verbal short-term memory. Recent work has indicated that this deficit is not caused by problems of audition, speech, or articulatory rehearsal within the phonological loop component of Baddeley and Hitch's working memory model. Given this, two experiments were conducted to investigate whether abnormally rapid decay underlies the deficit. In a first experiment, we attempted to vary the time available for decay using a modified serial recall procedure that had both verbal and visuospatial conditions. No evidence was found to suggest that forgetting is abnormally rapid in phonological memory in Down syndrome, but a selective phonological memory deficit was indicated. A second experiment further investigated possible problems of decay in phonological memory, restricted to item information. The results indicated that individuals with Down syndrome do not show atypically rapid item forgetting from phonological memory but may have a limited-capacity verbal short-term memory system.

Stygofauna enhance prokaryotic transport in groundwater ecosystems.

PubMed

Smith, Renee J; Paterson, James S; Launer, Elise; Tobe, Shanan S; Morello, Eliesa; Leijs, Remko; Marri, Shashikanth; Mitchell, James G

2016-09-06

More than 97% of the world's freshwater reserves are found in aquifers, making groundwater one of the most important resources on the planet. Prokaryotic communities in groundwater underpin the turnover of energy and matter while also maintaining groundwater purity. Thus, knowledge of microbial transport in the subsurface is crucial for maintaining groundwater health. Here, we describe for the first time the importance of stygofauna as vectors for prokaryotes. The "hitch-hiking" prokaryotes associated with stygofauna may be up to 5 orders of magnitude higher in abundance and transported up to 34× faster than bulk groundwater flow. We also demonstrate that prokaryotic diversity associated with stygofauna may be higher than that of the surrounding groundwater. Stygofauna are a newly recognized prokaryotic niche in groundwater ecosystems that have the potential to transport remediating, water purifying and pathogenic prokaryotes. Therefore, stygofauna may influence ecosystem dynamics and health at a microbial level, and at a larger scale could be a new source of prokaryotic diversity in groundwater ecosystems.

Population genomics of intrapatient HIV-1 evolution

PubMed Central

Zanini, Fabio; Brodin, Johanna; Thebo, Lina; Lanz, Christa; Bratt, Göran; Albert, Jan; Neher, Richard A

2015-01-01

Many microbial populations rapidly adapt to changing environments with multiple variants competing for survival. To quantify such complex evolutionary dynamics in vivo, time resolved and genome wide data including rare variants are essential. We performed whole-genome deep sequencing of HIV-1 populations in 9 untreated patients, with 6-12 longitudinal samples per patient spanning 5-8 years of infection. The data can be accessed and explored via an interactive web application. We show that patterns of minor diversity are reproducible between patients and mirror global HIV-1 diversity, suggesting a universal landscape of fitness costs that control diversity. Reversions towards the ancestral HIV-1 sequence are observed throughout infection and account for almost one third of all sequence changes. Reversion rates depend strongly on conservation. Frequent recombination limits linkage disequilibrium to about 100bp in most of the genome, but strong hitch-hiking due to short range linkage limits diversity. DOI: http://dx.doi.org/10.7554/eLife.11282.001 PMID:26652000

Stygofauna enhance prokaryotic transport in groundwater ecosystems

PubMed Central

Smith, Renee J.; Paterson, James S.; Launer, Elise; Tobe, Shanan S.; Morello, Eliesa; Leijs, Remko; Marri, Shashikanth; Mitchell, James G.

2016-01-01

More than 97% of the world’s freshwater reserves are found in aquifers, making groundwater one of the most important resources on the planet. Prokaryotic communities in groundwater underpin the turnover of energy and matter while also maintaining groundwater purity. Thus, knowledge of microbial transport in the subsurface is crucial for maintaining groundwater health. Here, we describe for the first time the importance of stygofauna as vectors for prokaryotes. The “hitch-hiking” prokaryotes associated with stygofauna may be up to 5 orders of magnitude higher in abundance and transported up to 34× faster than bulk groundwater flow. We also demonstrate that prokaryotic diversity associated with stygofauna may be higher than that of the surrounding groundwater. Stygofauna are a newly recognized prokaryotic niche in groundwater ecosystems that have the potential to transport remediating, water purifying and pathogenic prokaryotes. Therefore, stygofauna may influence ecosystem dynamics and health at a microbial level, and at a larger scale could be a new source of prokaryotic diversity in groundwater ecosystems. PMID:27597322

Stygofauna enhance prokaryotic transport in groundwater ecosystems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Renee J.; Paterson, James S.; Launer, Elise

More than 97% of the world’s freshwater reserves are found in aquifers, making groundwater one of the most important resources on the planet. Prokaryotic communities in groundwater underpin the turnover of energy and matter while also maintaining groundwater purity. Thus, knowledge of microbial transport in the subsurface is crucial for maintaining groundwater health. Here, we describe for the first time the importance of stygofauna as vectors for prokaryotes. The “hitch-hiking” prokaryotes associated with stygofauna may be up to 5 orders of magnitude higher in abundance and transported up to 34× faster than bulk groundwater flow. We also demonstrate that prokaryoticmore » diversity associated with stygofauna may be higher than that of the surrounding groundwater. Stygofauna are a newly recognized prokaryotic niche in groundwater ecosystems that have the potential to transport remediating, water purifying and pathogenic prokaryotes. Furthermore, stygofauna may influence ecosystem dynamics and health at a microbial level, and at a larger scale could be a new source of prokaryotic diversity in groundwater ecosystems.« less

Stygofauna enhance prokaryotic transport in groundwater ecosystems

DOE PAGES

Smith, Renee J.; Paterson, James S.; Launer, Elise; ...

2016-09-06

More than 97% of the world’s freshwater reserves are found in aquifers, making groundwater one of the most important resources on the planet. Prokaryotic communities in groundwater underpin the turnover of energy and matter while also maintaining groundwater purity. Thus, knowledge of microbial transport in the subsurface is crucial for maintaining groundwater health. Here, we describe for the first time the importance of stygofauna as vectors for prokaryotes. The “hitch-hiking” prokaryotes associated with stygofauna may be up to 5 orders of magnitude higher in abundance and transported up to 34× faster than bulk groundwater flow. We also demonstrate that prokaryoticmore » diversity associated with stygofauna may be higher than that of the surrounding groundwater. Stygofauna are a newly recognized prokaryotic niche in groundwater ecosystems that have the potential to transport remediating, water purifying and pathogenic prokaryotes. Furthermore, stygofauna may influence ecosystem dynamics and health at a microbial level, and at a larger scale could be a new source of prokaryotic diversity in groundwater ecosystems.« less

Sward structure and nutritive value of Alexandergrass fertilized with nitrogen.

PubMed

Salvador, Paulo R; Pötter, Luciana; Rocha, Marta G; Hundertmarck, Anelise P; Sichonany, Maria José O; Amaral Neto, Luiz G; Negrini, Mateus; Moterle, Paulo H

2016-03-01

This experiment evaluated forage production, sward structure, stocking rate, weight gain per area and nutritive value of forage as grazed by beef heifers on Alexandergrass (Urochloa plantaginea (Link) Hitch) pasture fertilized with nitrogen (N): 0; 100; 200 or 300 kg of N/ha. The experiment was a completely randomized design following a repeated measurement arrangement. The experimental animals were Angus heifers with initial age and weight of 15 months and 241.5±5 kg, respectively. The grazing method was continuous, with put-and-take stocking. N utilization, regardless of the level, increase by 25% the daily forage accumulation rate and the weight gain per area by 23%. The level of 97.2 kg N/ha leads to a higher leaf blade mass and increases by 20% the leaf:stem ratio. Alterations in sward structure changes the nutritive value of forage as grazed. The utilization of 112.7 kg of N/ha allows the highest stocking rate (2049.8 kg of BW/ha), equivalent to 7.5 heifers per hectare.

Unique Offerings of the ISS as an Earth Observing Platform

NASA Technical Reports Server (NTRS)

Cooley, Victor M.

2013-01-01

The International Space Station offers unique capabilities for earth remote sensing. An established Earth orbiting platform with abundant power, data and commanding infrastructure, the ISS has been in operation for twelve years as a crew occupied science laboratory and offers low cost and expedited concept-to-operation paths for new sensing technologies. Plug in modularity on external platforms equipped with structural, power and data interfaces standardizes and streamlines integration and minimizes risk and start up difficulties. Data dissemination is also standardized. Emerging sensor technologies and instruments tailored for sensing of regional dynamics may not be worthy of dedicated platforms and launch vehicles, but may well be worthy of ISS deployment, hitching a ride on one of a variety of government or commercial visiting vehicles. As global acceptance of the urgent need for understanding Climate Change continues to grow, the value of ISS, orbiting in Low Earth Orbit, in complementing airborne, sun synchronous polar, geosynchronous and other platform remote sensing will also grow.

Lessons we learn from review of urological procedures performed during three decades in a spinal cord injury patient: a case report

PubMed Central

2009-01-01

Background We review urological procedures performed on a spinal cord injury patient during three decades. Case presentation A 23-year-old male patient sustained T-12 paraplegia in 1971. In 1972, intravenous urography showed both kidneys functioning well; division of external urethral sphincter was performed. In 1976, reimplantation of left ureter (Lich-Gregoir) was carried out for vesicoureteric reflux. As reflux persisted, left ureter was reimplanted by psoas hitch-Boari flap technique in 1978. This patient suffered from severe pain in legs; intrathecal injection of phenol was performed twice in 1979. The segment bearing the scarred spinal cord was removed in September 1982. This patient required continuous catheter drainage. Deep median sphincterotomy was performed in 1984. As the left kidney showed little function, left nephroureterectomy was performed in 1986. In an attempt to obviate the need for an indwelling catheter, bladder neck resection and tri-radiate sphincterotomy were carried out in 1989; but these procedures proved futile. UroLume prosthesis was inserted and splinted the urethra from prostatic apex to bulb in October 1990. As mucosa was apposing distal to stent, in November 1990, second UroLume stent was hitched inside distal end of first. In March 1991, urethroscopy showed the distal end of the distal stent had fragmented; loose wires were removed. In April 1991, this patient developed sweating, shivering and haematuria. Urine showed Pseudomonas. Suprapubic cystostomy was performed. Suprapubic cystostomy was done again the next day, as the catheter was pulled out accidentally during night. Subsequently, a 16 Fr Silastic catheter was passed per urethra and suprapubic catheter was removed. In July 1993, Urocoil stent was put inside UroLume stent with distal end of Urocoil stent lying free in urethra. In September 1993, this patient was struggling to pass urine. Urocoil stent had migrated to bladder; therefore, Urocoil stent was removed and a Memotherm stent was deployed. This patient continued to experience trouble with micturition; therefore, Memotherm stent was removed. Currently, wires of UroLume stent protrude in to urethra, which tend to puncture the balloon of urethral Foley catheter, especially when the patient performs manual evacuation of bowels. Conclusion We failed to implement intermittent catheterisation along with anti-cholinergic therapy. Instead, we performed several urological procedures with unsatisfactory outcome; the patient lost his left kidney. We believe that honest review of clinical practice will help towards learning from past mistakes. PMID:20062593

Lessons we learn from review of urological procedures performed during three decades in a spinal cord injury patient: a case report.

PubMed

Vaidyanathan, Subramanian; Soni, Bakul M; Hughes, Peter L; Singh, Gurpreet; Mansour, Paul; Oo, Tun

2009-12-16

We review urological procedures performed on a spinal cord injury patient during three decades. A 23-year-old male patient sustained T-12 paraplegia in 1971. In 1972, intravenous urography showed both kidneys functioning well; division of external urethral sphincter was performed. In 1976, reimplantation of left ureter (Lich-Gregoir) was carried out for vesicoureteric reflux. As reflux persisted, left ureter was reimplanted by psoas hitch-Boari flap technique in 1978. This patient suffered from severe pain in legs; intrathecal injection of phenol was performed twice in 1979. The segment bearing the scarred spinal cord was removed in September 1982. This patient required continuous catheter drainage. Deep median sphincterotomy was performed in 1984. As the left kidney showed little function, left nephroureterectomy was performed in 1986. In an attempt to obviate the need for an indwelling catheter, bladder neck resection and tri-radiate sphincterotomy were carried out in 1989; but these procedures proved futile. UroLume prosthesis was inserted and splinted the urethra from prostatic apex to bulb in October 1990. As mucosa was apposing distal to stent, in November 1990, second UroLume stent was hitched inside distal end of first. In March 1991, urethroscopy showed the distal end of the distal stent had fragmented; loose wires were removed. In April 1991, this patient developed sweating, shivering and haematuria. Urine showed Pseudomonas. Suprapubic cystostomy was performed. Suprapubic cystostomy was done again the next day, as the catheter was pulled out accidentally during night. Subsequently, a 16 Fr Silastic catheter was passed per urethra and suprapubic catheter was removed. In July 1993, Urocoil stent was put inside UroLume stent with distal end of Urocoil stent lying free in urethra. In September 1993, this patient was struggling to pass urine. Urocoil stent had migrated to bladder; therefore, Urocoil stent was removed and a Memotherm stent was deployed. This patient continued to experience trouble with micturition; therefore, Memotherm stent was removed. Currently, wires of UroLume stent protrude in to urethra, which tend to puncture the balloon of urethral Foley catheter, especially when the patient performs manual evacuation of bowels. We failed to implement intermittent catheterisation along with anti-cholinergic therapy. Instead, we performed several urological procedures with unsatisfactory outcome; the patient lost his left kidney. We believe that honest review of clinical practice will help towards learning from past mistakes.

In-field experiment of electro-hydraulic tillage depth draft-position mixed control on tractor

NASA Astrophysics Data System (ADS)

Han, Jiangyi; Xia, Changgao; Shang, Gaogao; Gao, Xiang

2017-12-01

The soil condition and condition of the plow affect the tillage resistance and the maximum traction of tractor. In order to improve the adaptability of tractor tillage depth control, a multi-parameter control strategy is proposed that included tillage depth target, draft force aim and draft-position mixed ratio. In the strategy, the resistance coefficient was used to adjust the draft force target. Then, based on a JINMA1204 tractor, the electro-hydraulic hitch prototype is constructed that could set control parameters.. The fuzzy controller of draft-position mixed control is designed. After that, in-field experiments of position control was carried on, and the result of experiment shows the error of tillage depth was less than ±20mm. The experiment of draft-position control shown that the draft force and the tillage depth could be adjust by multi-parameter such as tillage depth, resistance coefficient and draft-position mixed coefficient. So that, the multi-parameter control strategy could improve the adaptability of tillage depth control in various soils and plow condition.

The Picture of the Century with Floyd Thompsona and Ann Hitch Kilgore, Former Mayor of Hampton VA.

NASA Image and Video Library

1966-12-14

Langley Center Director Floyd Thompson shows Ann Kilgore the "picture of the century." This was the first picture of the earth taken from space. From Spaceflight Revolution: "On 23 August 1966 just as Lunar Orbiter I was about to pass behind the moon, mission controllers executed the necessary maneuvers to point the camera away from the lunar surface and toward the earth. The result was the world's first view of the earth from space. It was called "the picture of the century' and "the greatest shot taken since the invention of photography." Not even the color photos of the earth taken during the Apollo missions superseded the impact of this first image of our planet as a little island of life floating in the black and infinite sea of space." -- Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, (Washington: NASA, 1995), pp. 345-346. Mayor Ann Kilgore was married to NASA researcher Edwin Carroll Kilgore. Mrs, Kilgore was Mayor from 1963-1971 and again from 1974-1978.

Haloarcula hispanica CRISPR authenticates PAM of a target sequence to prime discriminative adaptation

PubMed Central

Li, Ming; Wang, Rui; Xiang, Hua

2014-01-01

The prokaryotic immune system CRISPR/Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated genes) adapts to foreign invaders by acquiring their short deoxyribonucleic acid (DNA) fragments as spacers, which guide subsequent interference to foreign nucleic acids based on sequence matching. The adaptation mechanism avoiding acquiring ‘self’ DNA fragments is poorly understood. In Haloarcula hispanica, we previously showed that CRISPR adaptation requires being primed by a pre-existing spacer partially matching the invader DNA. Here, we further demonstrate that flanking a fully-matched target sequence, a functional PAM (protospacer adjacent motif) is still required to prime adaptation. Interestingly, interference utilizes only four PAM sequences, whereas adaptation-priming tolerates as many as 23 PAM sequences. This relaxed PAM selectivity explains how adaptation-priming maximizes its tolerance of PAM mutations (that escape interference) while avoiding mis-targeting the spacer DNA within CRISPR locus. We propose that the primed adaptation, which hitches and cooperates with the interference pathway, distinguishes target from non-target by CRISPR ribonucleic acid guidance and PAM recognition. PMID:24803673

Automated Aerial Refueling Hitches a Ride on AFF

NASA Technical Reports Server (NTRS)

Hansen, Jennifer L.; Murray, James E.; Bever, Glenn; Campos, Norma V.; Schkolnik, Gerard

2007-01-01

The recent introduction of uninhabited aerial vehicles [UAVs (basically, remotely piloted or autonomous aircraft)] has spawned new developments in autonomous operation and posed new challenges. Automated aerial refueling (AAR) is a capability that will enable UAVs to travel greater distances and loiter longer over targets. NASA Dryden Flight Research Center, in cooperation with the Defense Advanced Research Projects Agency (DARPA), the Naval Air Systems Command (NAVAIR), the Naval Air Force Pacific Fleet, and the Air Force Research Laboratory, rapidly conceived and accomplished an AAR flight research project focused on collecting a unique, high-quality database on the dynamics of the hose and drogue of an aerial refueling system. This flight-derived database would be used to validate mathematical models of the dynamics in support of design and analysis of AAR systems for future UAVs. The project involved the use of two Dryden F/A-18 airplanes and an S-3 hose-drogue refueling store on loan from the Navy. In this year-long project, which was started on October 1, 2002, 583 research maneuvers were completed during 23 flights.

High-throughput continuous hydrothermal synthesis of an entire nanoceramic phase diagram.

PubMed

Weng, Xiaole; Cockcroft, Jeremy K; Hyett, Geoffrey; Vickers, Martin; Boldrin, Paul; Tang, Chiu C; Thompson, Stephen P; Parker, Julia E; Knowles, Jonathan C; Rehman, Ihtesham; Parkin, Ivan; Evans, Julian R G; Darr, Jawwad A

2009-01-01

A novel High-Throughput Continuous Hydrothermal (HiTCH) flow synthesis reactor was used to make directly and rapidly a 66-sample nanoparticle library (entire phase diagram) of nanocrystalline Ce(x)Zr(y)Y(z)O(2-delta) in less than 12 h. High resolution PXRD data were obtained for the entire heat-treated library (at 1000 degrees C/1 h) in less than a day using the new robotic beamline I11, located at Diamond Light Source (DLS). This allowed Rietveld-quality powder X-ray diffraction (PXRD) data collection of the entire 66-sample library in <1 day. Consequently, the authors rapidly mapped out phase behavior and sintering behaviors for the entire library. Out of the entire 66-sample heat-treated library, the PXRD data suggests that 43 possess the fluorite structure, of which 30 (out of 36) are ternary compositions. The speed, quantity and quality of data obtained by our new approach, offers an exciting new development which will allow structure-property relationships to be accessed for nanoceramics in much shorter time periods.

Proposal of custom made wrist orthoses based on 3D modelling and 3D printing.

PubMed

Abreu de Souza, Mauren; Schmitz, Cristiane; Marega Pinhel, Marcelo; Palma Setti, Joao A; Nohama, Percy

2017-07-01

Accessibility to three-dimensional (3D) technologies, such as 3D scanning systems and additive manufacturing (like 3D printers), allows a variety of 3D applications. For medical applications in particular, these modalities are gaining a lot of attention enabling several opportunities for healthcare applications. The literature brings several cases applying both technologies, but none of them focus on the spreading of how this technology could benefit the health segment. This paper proposes a new methodology, which employs both 3D modelling and 3D printing for building orthoses, which could better fit the demands of different patients. Additionally, there is an opportunity for sharing expertise, as it represents a trendy in terms of the maker-movement. Therefore, as a result of the proposed approach, we present a case study based on a volunteer who needs an immobilization orthosis, which was built for exemplification of the whole process. This proposal also employs freely available 3D models and software, having a strong social impact. As a result, it enables the implementation and effective usability for a variety of built to fit solutions, hitching useful and smarter technologies for the healthcare sector.

Interpositional Gap Arthroplasty by Versatile Pedicled Temporalis Myofascial Flap in the Management of Temporomandibular Joint Ankylosis- A Case Series Study.

PubMed

Aneja, Vikas; Raval, Rushik; Bansal, Anupam; Kumawat, Vinod; Kaur, Jasleen; Shaikh, Ahemer Arif

2016-10-01

Temporomandibular Joint (TMJ) ankylosis is a situation in which the mandibular condyle is fused to the glenoid fossa by bone or fibrous tissue. The management of TMJ ankylosis has a complicated chore and it is challenging for the maxillofacial surgeon because of technical hitches and high rate of re-ankylosis. Interpositional gap arthroplasty is one of the modalities for its management. A range of inter-positional materials have been used to avert recurrence after gap arthroplasty in TMJ ankylosis. The aim of this series was to evaluate the effectiveness of the temporomyofacial flap in the treatment of TMJ ankylosis as an interpositional gap arthroplasty. A total of 10 cases with unilateral TMJ ankylosis were treated by interpositional gap arthroplasty by pedicled temporalis myofacial flap and evaluated with a follow-up of 6 months to 5 years (Mean 3.3 years) for the functional stability of TMJ. All the patients were successfully treated. There were no signs of recurrence in any patients up to last follow up visit. The result showed that temporalis myofascial flap is a preferable choice for inter-positional gap arthroplasty which proves its versatility as an inter-positional material.

Interpositional Gap Arthroplasty by Versatile Pedicled Temporalis Myofascial Flap in the Management of Temporomandibular Joint Ankylosis- A Case Series Study

PubMed Central

Aneja, Vikas; Bansal, Anupam; Kumawat, Vinod; Kaur, Jasleen; Shaikh, Ahemer Arif

2016-01-01

Temporomandibular Joint (TMJ) ankylosis is a situation in which the mandibular condyle is fused to the glenoid fossa by bone or fibrous tissue. The management of TMJ ankylosis has a complicated chore and it is challenging for the maxillofacial surgeon because of technical hitches and high rate of re-ankylosis. Interpositional gap arthroplasty is one of the modalities for its management. A range of inter-positional materials have been used to avert recurrence after gap arthroplasty in TMJ ankylosis. The aim of this series was to evaluate the effectiveness of the temporomyofacial flap in the treatment of TMJ ankylosis as an interpositional gap arthroplasty. A total of 10 cases with unilateral TMJ ankylosis were treated by interpositional gap arthroplasty by pedicled temporalis myofacial flap and evaluated with a follow-up of 6 months to 5 years (Mean 3.3 years) for the functional stability of TMJ. All the patients were successfully treated. There were no signs of recurrence in any patients up to last follow up visit. The result showed that temporalis myofascial flap is a preferable choice for inter-positional gap arthroplasty which proves its versatility as an inter-positional material. PMID:27891496

STS-71 Pilot Charles J. Precort arrival in T-38

NASA Technical Reports Server (NTRS)

1995-01-01

STS-71 Pilot Charles J. Precourt arrives at the KSC Shuttle Landing Facility in one of the T-38 aircraft traditionally flown by the astronaut corps. The seven STS-71 crew members flew into KSC from Johnson Space Center as final preparations are under way toward the scheduled liftoff on June 23 of the Space Shuttle Atlantis on the first mission to dock with the Russian Space Station Mir. KSC-95EC-870 - Mir 19 Flight Engineer Nikolai M. Budarin arrives at KSC Mir 19 Flight Engineer Nikolai M. Budarin hitches a ride with STS-71 Pilot Charles J. Precourt in a T-38. Budarin, Precourt and the rest of the STS-71 crew arrived at KSC's Shuttle Landing Facility the same day the countdown clock began ticking toward a scheduled liftoff on Friday, June 23. During the historic flight of the Space Shuttle Atlantis on STS- 71, the crew will perform the first U.S. docking with the Russian Space Station Mir. Budarin and Mir 19 Mission Commander Anatoly Solovyev will transfer to Mir during the flight, and the three crew members currently on Mir will return to Earth in the orbiter.

Transition from Exponential to Power Law Income Distributions in a Chaotic Market

NASA Astrophysics Data System (ADS)

Pellicer-Lostao, Carmen; Lopez-Ruiz, Ricardo

Economy is demanding new models, able to understand and predict the evolution of markets. To this respect, Econophysics offers models of markets as complex systems, that try to comprehend macro-, system-wide states of the economy from the interaction of many agents at micro-level. One of these models is the gas-like model for trading markets. This tries to predict money distributions in closed economies and quite simply, obtains the ones observed in real economies. However, it reveals technical hitches to explain the power law distribution, observed in individuals with high incomes. In this work, nonlinear dynamics is introduced in the gas-like model in an effort to overcomes these flaws. A particular chaotic dynamics is used to break the pairing symmetry of agents (i, j) ⇔ (j, i). The results demonstrate that a "chaotic gas-like model" can reproduce the Exponential and Power law distributions observed in real economies. Moreover, it controls the transition between them. This may give some insight of the micro-level causes that originate unfair distributions of money in a global society. Ultimately, the chaotic model makes obvious the inherent instability of asymmetric scenarios, where sinks of wealth appear and doom the market to extreme inequality.

Is short-term memory involved in decision making? Evidence from a short-term memory patient.

PubMed

Gozzi, Marta; Papagno, Costanza

2007-03-01

It is reasonable to suggest that working memory (WM; Baddeley & Hitch, 1974) is involved in decision making, as decision making is dependent on the ability to remember and update past choices and outcomes. However, contradictory results have been reported in the literature concerning the role of two of its components, namely the central executive and the phonological loop. In order to investigate the role of these components in the decision-making process, we tested a patient with intact central executive but impaired phonological loop on a laboratory decision-making task involving hypothetical gambles (gambling task, GT). When tested in a no-load condition (simple keypress task), her performance was not significantly different from that of matched controls. We also verified whether her performance would be affected differently by memory-load when compared with control subjects. The memory task (holding a string of letters in memory) loaded WM without incurring number-number interference. When the memory-load was imposed during the GT, both the patient and the controls showed a decline in performance, but the strategy they adopted differed. Possible explanations are discussed. In conclusion, our results suggest that the phonological loop is not directly involved in decision making.

"God bless General Péron": DDT and the endgame of malaria eradication in Argentina in the 1940s.

PubMed

Carter, Eric D

2009-01-01

This article explores the politics of malaria eradication in Argentina during the first government of Juan D. Perón. The article develops the theme of historical convergence to understand the rapid mobilization and success of the climactic battle against malaria in Northwest Argentina. The nearly complete eradication of malaria in Argentina resulted from a combination of three factors. First, Carlos Alvarado, the director of Argentina's Malaria Service, had already developed a solid but flexible organizational base that allowed a dramatic change in control strategy. Second, an infusion of new technologies, especially DDT but also motor vehicles, was instrumental. Lastly, a radical reorientation of national public health policy in the 1940s, under the direction of Perón and his health minister, Ramón Carrillo, encouraged eradication. These figures embraced and refashioned long-standing organicist ideologies that hitched the strength of the nation-state to the health and vigor of its ordinary citizens. This ideological orientation was reflected in bold, populist political strategies that showcased swift, massive, and expensive public health campaigns, including malaria eradication. In the conclusion, the article explores the ambiguous connections between malaria eradication and an ecological perspective on the disease.

Optimization of vehicle-trailer connection systems

NASA Astrophysics Data System (ADS)

Sorge, F.

2016-09-01

The three main requirements of a vehicle-trailer connection system are: en route stability, over- or under-steering restraint, minimum off-tracking along curved path. Linking the two units by four-bar trapeziums, wider stability margins may be attained in comparison with the conventional pintle-hitch for both instability types, divergent or oscillating. The stability maps are traced applying the Hurwitz method or the direct analysis of the characteristic equation at the instability threshold. Several types of four-bar linkages may be quickly tested, with the drawbars converging towards the trailer or the towing unit. The latter configuration appears preferable in terms of self-stability and may yield high critical speeds by optimising the geometrical and physical properties. Nevertheless, the system stability may be improved in general by additional vibration dampers in parallel with the connection linkage. Moreover, the four-bar connection may produce significant corrections of the under-steering or over-steering behaviour of the vehicle-train after a steering command from the driver. The off- tracking along the curved paths may be also optimized or kept inside prefixed margins of acceptableness. Activating electronic stability systems if necessary, fair results are obtainable for both the steering conduct and the off-tracking.

Feature binding and attention in working memory: a resolution of previous contradictory findings.

PubMed

Allen, Richard J; Hitch, Graham J; Mate, Judit; Baddeley, Alan D

2012-01-01

We aimed to resolve an apparent contradiction between previous experiments from different laboratories, using dual-task methodology to compare effects of a concurrent executive load on immediate recognition memory for colours or shapes of items or their colour-shape combinations. Results of two experiments confirmed previous evidence that an irrelevant attentional load interferes equally with memory for features and memory for feature bindings. Detailed analyses suggested that previous contradictory evidence arose from limitations in the way recognition memory was measured. The present findings are inconsistent with an earlier suggestion that feature binding takes place within a multimodal episodic buffer Baddeley, ( 2000 ) and support a subsequent account in which binding takes place automatically prior to information entering the episodic buffer Baddeley, Allen, & Hitch, ( 2011 ). Methodologically, the results suggest that different measures of recognition memory performance (A', d', corrected recognition) give a converging picture of main effects, but are less consistent in detecting interactions. We suggest that this limitation on the reliability of measuring recognition should be taken into account in future research so as to avoid problems of replication that turn out to be more apparent than real.

Vertical transmission of Prunus necrotic ringspot virus: hitch-hiking from gametes to seedling.

PubMed

Amari, Khalid; Burgos, Lorenzo; Pallás, Vicente; Sánchez-Pina, Maria Amelia

2009-07-01

The aim of this work was to follow Prunus necrotic ringspot virus (PNRSV) infection in apricot reproductive tissues and transmission of the virus to the next generation. For this, an analysis of viral distribution in apricot reproductive organs was carried out at different developmental stages. PNRSV was detected in reproductive tissues during gametogenesis. The virus was always present in the nucellus and, in some cases, in the embryo sac. Studies within infected seeds at the embryo globular stage revealed that PNRSV infects all parts of the seed, including embryo, endosperm and testa. In the torpedo and bent cotyledon developmental stages, high concentrations of the virus were detected in the testa and endosperm. At seed maturity, PNRSV accumulated slightly more in the embryo than in the cotyledons. In situ hybridization showed the presence of PNRSV RNA in embryos obtained following hand-pollination of virus-free pistils with infected pollen. Interestingly, tissue-printing from fruits obtained from these pistils showed viral RNA in the periphery of the fruits, whereas crosses between infected pistils and infected pollen resulted in a total invasion of the fruits. Taken together, these results shed light on the vertical transmission of PNRSV from gametes to seedlings.

In vitro and in situ characterization of arthroscopic loop security and knot security of braided polyblend sutures: a biomechanical study.

PubMed

Armstrong, Lucas C; Chong, Alexander; Livermore, Ryan W; Prohaska, Daniel J; Doyon, Amanda N; Wooley, Paul H

2015-04-01

We conducted a study to evaluate biomechanical performance during destructive testing of several different suture materials in various arthroscopic knot configurations under both in vitro and in situ conditions. Surgeons of different levels of experience tied the knots. Three different arthroscopic knots (static surgeon's, Weston, Tennessee slider) with 3 reverse half-hitches on alternating posts were tested using Fiberwire, ForceFiber, Orthocord, and Ultrabraid suture materials under both in vitro and in situ (blood plasma at 37°C) conditions. Three surgeons of different experience levels tied the knots on a post 30 mm in circumference. A single load-to-failure test was performed. There were no significant in vitro-in situ differences for Ultrabraid in the different knot configurations or with the different experience levels. Surgeon B (intermediate experience) showed no significant differences between test conditions for any knot configuration or suture material. With Tennessee slider knots, surgeon C (least experience) showed significantly lower clinical failure load under both test conditions and had a higher percentage of complete knot slippage. Surgeon B had no knot slippage with use of Fiberwire. Both the aqueous environment and the surgeon's familiarity with certain knots have an effect on knot security.

Fractionating the neural correlates of individual working memory components underlying arithmetic problem solving skills in children

PubMed Central

Metcalfe, Arron W. S.; Ashkenazi, Sarit; Rosenberg-Lee, Miriam; Menon, Vinod

2013-01-01

Baddeley and Hitch’s multi-component working memory (WM) model has played an enduring and influential role in our understanding of cognitive abilities. Very little is known, however, about the neural basis of this multi-component WM model and the differential role each component plays in mediating arithmetic problem solving abilities in children. Here, we investigate the neural basis of the central executive (CE), phonological (PL) and visuo-spatial (VS) components of WM during a demanding mental arithmetic task in 7–9 year old children (N=74). The VS component was the strongest predictor of math ability in children and was associated with increased arithmetic complexity-related responses in left dorsolateral and right ventrolateral prefrontal cortices as well as bilateral intra-parietal sulcus and supramarginal gyrus in posterior parietal cortex. Critically, VS, CE and PL abilities were associated with largely distinct patterns of brain response. Overlap between VS and CE components was observed in left supramarginal gyrus and no overlap was observed between VS and PL components. Our findings point to a central role of visuo-spatial WM during arithmetic problem-solving in young grade-school children and highlight the usefulness of the multi-component Baddeley and Hitch WM model in fractionating the neural correlates of arithmetic problem solving during development. PMID:24212504

[Rape by 2 assaillants and gang rape in Montreal].

PubMed

Lamontagne, Y; Boyer, R; Lamontagne, C; Giroux, J

1984-11-01

A survey was conducted in 230 cases of rape and rape attempts heard in the Judicial District of Montreal between January 1975 and May 1978. Data were compiled from the 30 assaults including two or more assaillants. Results show that in cases of rape committed by two men the aggressors are older than gang rapists, meet the victim mainly in her flat or in a bar, and rape her in her own home, in a car or a hotel. In these cases, voyeurism seems to be an important factor since, most of the time, rape is committed by only one of the two aggressors. On the other hand, gang rapists are younger, meet the victim in public places, on the street or when she is hitch-hiking and attack her in one of the aggressors' house, in public places or on the street. Exhibitionism seems more present in this group of rapists. For both groups the victims are mainly single, younger than the aggressors and have diverse occupations. Finally, regarding the legal outcome half of the subjects were liberated or acquitted in both groups. Rape committed by two men had never been studied or compared with gang rape up until now. Results of this survey show dynamic and demographic differences between these two groups of sexual delinquents.

Gas fired boilers: Perspective for near future fuel composition and impact on burner design process

NASA Astrophysics Data System (ADS)

Schiro, Fabio; Stoppato, Anna; Benato, Alberto

2017-11-01

The advancements on gas boiler technology run in parallel with the growth of renewable energy production. The renewable production will impact on the fuel gas quality, since the gas grid will face an increasing injection of alternative fuels (biogas, biomethane, hydrogen). Biogas allows producing energy with a lower CO2 impact; hydrogen production by electrolysis can mitigate the issues related to the mismatch between energy production by renewable and energy request. These technologies will contribute to achieve the renewable production targets, but the impact on whole fuel gas production-to-consumption chain must be evaluated. In the first part of this study, the Authors present the future scenario of the grid gas composition and the implications on gas fed appliances. Given that the widely used premixed burners are currently designed mainly by trial and error, a broader fuel gas quality range means an additional hitch on this design process. A better understanding and structuring of this process is helpful for future appliance-oriented developments. The Authors present an experimental activity on a premixed condensing boiler setup. A test protocol highlighting the burners' flexibility in terms of mixture composition is adopted and the system fuel flexibility is characterized around multiple reference conditions.

Iatrogenic ureteric injuries: approaches to etiology and management.

PubMed

Watterson, J D; Mahoney, J E; Futter, N G; Gaffield, J

1998-10-01

Injury to the ureter is a risk of any pelvic or abdominal surgery, including laparoscopy and ureteroscopy. The morbidity associated with such injury may be serious, resulting in increased hospital stay, compromise of the original surgical outcome, secondary invasive interventions, reoperation, potential loss of renal function and deterioration of the patient's quality of life. Management of ureteric injuries, in conjunction with frank and open dialogue with the patient, can lead to an optimal outcome. For ureteral ligation, removal of the suture and assessment of ureteral viability are recommended, with surgical correction if necessary. For partial transection primary closure is suggested over stent placement. For uncomplicated upper- and middle-third ureteral injury ureteroureterostomy is the procedure of choice. For injuries above the pelvic brim several procedures are available: ureteroureterostomy, ureteroileal interposition and nephrectomy. For injuries below the pelvic brim ureteroneocystostomy is recommended with a psoas hitch or Boari bladder flap. To decrease the incidence of iatrogenic ureteral injury, a sound knowledge of abdominal and pelvic anatomy is the best prevention. If the proposed operation is likely to be close to the ureter, the ureter should be identified at the pelvic brim. If the dissection is likely to be difficult, preoperative intravenous pyelography and placement of a ureteral catheter may help in identifying and protecting the ureter.

Iatrogenic ureteric injuries: approaches to etiology and management

PubMed Central

Watterson, James D.; Mahoney, John E.; Futter, Norman G.; Gaffield, Johanna

1998-01-01

Injury to the ureter is a risk of any pelvic or abdominal surgery, including laparoscopy and ureteroscopy. The morbidity associated with such injury may be serious, resulting in increased hospital stay, compromise of the original surgical outcome, secondary invasive interventions, reoperation, potential loss of renal function and deterioration of the patient’s quality of life. Management of ureteric injuries, in conjunction with frank and open dialogue with the patient, can lead to an optimal outcome. For ureteral ligation, removal of the suture and assessment of ureteral viability are recommended, with surgical correction if necessary. For partial transection primary closure is suggested over stent placement. For uncomplicated upper- and middle-third ureteral injury ureteroureterostomy is the procedure of choice. For injuries above the pelvic brim several procedures are available: ureteroureterostomy, ureteroileal interposition and nephrectomy. For injuries below the pelvic brim ureteroneocystostomy is recommended with a psoas hitch or Boari bladder flap. To decrease the incidence of iatrogenic ureteral injury, a sound knowledge of abdominal and pelvic anatomy is the best prevention. If the proposed operation is likely to be close to the ureter, the ureter should be identified at the pelvic brim. If the dissection is likely to be difficult, preoperative intravenous pyelography and placement of a ureteral catheter may help in identifying and protecting the ureter. PMID:9793505

Remote sensing new model for monitoring the east Asian migratory locust infections based on its breeding circle

NASA Astrophysics Data System (ADS)

Han, Xiuzhen; Ma, Jianwen; Bao, Yuhai

2006-12-01

Currently the function of operational locust monitor system mainly focused on after-hazards monitoring and assessment, and to found the way effectively to perform early warning and prediction has more practical meaning. Through 2001, 2002 two years continuously field sample and statistics for locusts eggs hatching, nymph growth, adults 3 phases observation, sample statistics and calculation, spectral measurements as well as synchronically remote sensing data processing we raise the view point of Remote Sensing three stage monitor the locust hazards. Based on the point of view we designed remote sensing monitor in three stages: (1) during the egg hitching phase remote sensing can retrieve parameters of land surface temperature (LST) and soil moisture; (2) during nymph growth phase locust increases appetite greatly and remote sensing can calculate vegetation index, leaf area index, vegetation cover and analysis changes; (3) during adult phase the locust move and assembly towards ponds and water ditches as well as less than 75% vegetation cover areas and remote sensing combination with field data can monitor and predicts potential areas for adult locusts to assembly. In this way the priority of remote sensing technology is elaborated effectively and it also provides technique support for the locust monitor system. The idea and techniques used in the study can also be used as reference for other plant diseases and insect pests.

Visual Semantic Based 3D Video Retrieval System Using HDFS.

PubMed

Kumar, C Ranjith; Suguna, S

2016-08-01

This paper brings out a neoteric frame of reference for visual semantic based 3d video search and retrieval applications. Newfangled 3D retrieval application spotlight on shape analysis like object matching, classification and retrieval not only sticking up entirely with video retrieval. In this ambit, we delve into 3D-CBVR (Content Based Video Retrieval) concept for the first time. For this purpose, we intent to hitch on BOVW and Mapreduce in 3D framework. Instead of conventional shape based local descriptors, we tried to coalesce shape, color and texture for feature extraction. For this purpose, we have used combination of geometric & topological features for shape and 3D co-occurrence matrix for color and texture. After thriving extraction of local descriptors, TB-PCT (Threshold Based- Predictive Clustering Tree) algorithm is used to generate visual codebook and histogram is produced. Further, matching is performed using soft weighting scheme with L 2 distance function. As a final step, retrieved results are ranked according to the Index value and acknowledged to the user as a feedback .In order to handle prodigious amount of data and Efficacious retrieval, we have incorporated HDFS in our Intellection. Using 3D video dataset, we future the performance of our proposed system which can pan out that the proposed work gives meticulous result and also reduce the time intricacy.

ALOS PALSAR Winter Coherence and Summer Intensities for Large Scale Forest Monitoring in Siberia

NASA Astrophysics Data System (ADS)

Thiel, Christian; Thiel, Carolin; Santoro, Maurizio; Schmullius, Christiane

2008-11-01

In this paper summer intensity and winter coherence images are used for large scale forest monitoring. The intensities (FBD HH/HV) have been acquired during summer 2007 and feature the K&C intensity stripes [1]. The processing consisted of radiometric calibration, orthorectification, and topographic normalisation. The coherence has been estimated from interferometric pairs with 46-days repeat-pass intervals. The pairs have been acquired during the winters 2006/2007 and 2007/2008. During both winters suited weather conditions have been reported. Interferometric processing consisted of SLC co-registration at sub-pixel level, common-band filtering in range and azimuth and generation of a differential interferogram, which was used in the coherence estimation procedure based on adaptive estimation. All images were geocoded using SRTM data. The pixel size of the final SAR products is 50 m x 50 m. It could already be demonstrated, that by using PALSAR intensities and winter coherence forest and non-forest can be clearly separated [2]. By combining both data types hardly any overlap of the class signatures was detected, even though the analysis was conducted on pixel level and no speckle filter has been applied. Thus, the delineation of a forest cover mask could be executed operationally. The major hitch is the definition of a biomass threshold for regrowing forest to be distinguished as forest.

Early experience with open heart surgery in a pioneer private hospital in West Africa: the Biket medical centre experience.

PubMed

Onakpoya, Uvie Ufuoma; Adenle, Adebisi David; Adenekan, Anthony Taiwo

2017-01-01

More than forty years after the first open heart surgery in Nigeria, all open heart surgeries were carried out in government-owned hospitals before the introduction of such surgeries in 2013 at Biket Medical Centre, a privately owned hospital in Osogbo, South-western Nigeria. The aim of this paper is to review our initial experience with open heart surgery in this private hospital. All patients who underwent open heart surgery between August 2013 and January 2014 were included in this prospective study. The medical records of the patients were examined and data on age, sex, diagnosis, type of surgery, cardiopulmonary bypass details, complications and length of hospital stay were extracted and the data was analysed using SPSS version 16. Eighteen patients comprising of 12 males and 6 females with ages ranging between 8 months and 52 years (mean= of 15.7 +/- 15 years) were studied. Pericardial patch closure of isolated ventricular septal defect was done in 7 patients (38.9%) while total correction of isolated tetralogy of Fallot was carried out in 5 patients (27.8%). Two patients had mitral valve repair for rheumatic mitral regurgitation. Sixty day mortality was 0%. Safe conduct of open heart surgery in the private hospital setting is feasible in Nigeria. It may be our only guarantee of hitch free and sustainable cardiac surgery.

Exploration of a 'double-jeopardy' hypothesis within working memory profiles for children with specific language impairment.

PubMed

Briscoe, J; Rankin, P M

2009-01-01

Children with specific language impairment (SLI) often experience difficulties in the recall and repetition of verbal information. Archibald and Gathercole (2006) suggested that children with SLI are vulnerable across two separate components of a tripartite model of working memory (Baddeley and Hitch 1974). However, the hierarchical relationship between the 'slave' systems (temporary storage) and the central executive components places a particular challenge for interpreting working memory profiles within a tripartite model. This study aimed to examine whether a 'double-jeopardy' assumption is compatible with a hierarchical relationship between the phonological loop and central executive components of the working memory model in children with SLI. If a strong double-jeopardy assumption is valid for children with SLI, it was predicted that raw scores of working memory tests thought to tap phonological loop and central executive components of tripartite working memory would be lower than the scores of children matched for chronological age and those of children matched for language level, according to independent sources of constraint. In contrast, a hierarchical relationship would imply that a weakness in a slave component of working memory (the phonological loop) would also constrain performance on tests tapping a super-ordinate component (central executive). This locus of constraint would predict that scores of children with SLI on working memory tests that tap the central executive would be weaker relative to the scores of chronological age-matched controls only. Seven subtests of the Working Memory Test Battery for Children (Digit recall, Word recall, Non-word recall, Word matching, Listening recall, Backwards digit recall and Block recall; Pickering and Gathercole 2001) were administered to 14 children with SLI recruited via language resource bases and specialist schools, as well as two control groups matched on chronological age and vocabulary level, respectively. Mean group differences were ascertained by directly comparing raw scores on memory tests linked to different components of the tripartite model using a series of multivariate analyses. The majority of working memory scores of the SLI group were depressed relative to chronological age-matched controls, with the exception of spatial recall (block tapping) and word (order) matching tasks. Marked deficits in serial recall of words and digits were evident, with the SLI group scoring more poorly than the language-ability matched control group on these measures. Impairments of the SLI group on phonological loop tasks were robust, even when covariance with executive working memory scores was accounted for. There was no robust effect of group on complex working memory (central executive) tasks, despite a slight association between listening recall and phonological loop measures. A predominant feature of the working memory profile of SLI was a marked deficit on phonological loop tasks. Although scores on complex working memory tasks were also depressed, there was little evidence for a strong interpretation of double-jeopardy within working memory profiles for these children, rather these findings were consistent with an interpretation of a constraint on phonological loop for children with SLI that operated at all levels of a hierarchical tripartite model of working memory (Baddeley and Hitch 1974). These findings imply that low scores on complex working memory tasks alone do not unequivocally imply an independent deficit in central executive (domain-general) resources of working memory and should therefore be treated cautiously in a clinical context.

Amodal processing in human prefrontal cortex.

PubMed

Tamber-Rosenau, Benjamin J; Dux, Paul E; Tombu, Michael N; Asplund, Christopher L; Marois, René

2013-07-10

Information enters the cortex via modality-specific sensory regions, whereas actions are produced by modality-specific motor regions. Intervening central stages of information processing map sensation to behavior. Humans perform this central processing in a flexible, abstract manner such that sensory information in any modality can lead to response via any motor system. Cognitive theories account for such flexible behavior by positing amodal central information processing (e.g., "central executive," Baddeley and Hitch, 1974; "supervisory attentional system," Norman and Shallice, 1986; "response selection bottleneck," Pashler, 1994). However, the extent to which brain regions embodying central mechanisms of information processing are amodal remains unclear. Here we apply multivariate pattern analysis to functional magnetic resonance imaging (fMRI) data to compare response selection, a cognitive process widely believed to recruit an amodal central resource across sensory and motor modalities. We show that most frontal and parietal cortical areas known to activate across a wide variety of tasks code modality, casting doubt on the notion that these regions embody a central processor devoid of modality representation. Importantly, regions of anterior insula and dorsolateral prefrontal cortex consistently failed to code modality across four experiments. However, these areas code at least one other task dimension, process (instantiated as response selection vs response execution), ensuring that failure to find coding of modality is not driven by insensitivity of multivariate pattern analysis in these regions. We conclude that abstract encoding of information modality is primarily a property of subregions of the prefrontal cortex.

Ureterovaginal fistula--etiological factors and outcome.

PubMed

Murtaza, Badar; Mahmood, Arshad; Niaz, Waqar Azim; Akmal, Muhammad; Ahmad, Hussain; Saeed, Saira

2012-10-01

To assess the etiological factors and the outcome of ureterovaginal fistula in an urban setting. The observational study was conducted at the Armed Forces Institute of Urology, Military Hospital, Rawalpindi, from January 2009 to January 2011. All the patients of uretero-vaginal fistula at the centre were included on the basis of non-probability purposive sampling. The etiology, clinical presentation and the investigative procedures were recorded. The operative modality contemplated was noted and post-operative results were evaluated. The data was entered in a structured proforma and analysed for descriptive statistics using SPSS version 14.0. Seventeen cases of ureterovaginal fistula were recorded. Amongst these 10 (58.8%) were post-hysterectomy, while 7 (41.1%) cases post-caesarean section. The emergency procedures performed by the residents/junior registrars contributed 12 (70.2%) of the cases. All these patients were treated surgically; 14 (82.3%) were managed with ureteroneocystostomy, 2 (11.7%) required Boari Flap reconstruction, and in psoas hitch was performed in 1 (5.8%) case. The time of intervention was 4 - 12 weeks (9.76 +/- 2.223). Post-operatively, only 1 (5.8%) case had superficial wound infection and 1 (5.8%) urinary tract infection. All the patients remained dry with a follow-up period of 3 - 24 months (mean 12.24 +/- 6.879). Ureterovaginal fistula is one of the complications of emergency procedures, especially in the hands of inexperienced surgeons. Prompt diagnosis and surgical intervention produce excellent results. Intervention can be done safely as early as 4 weeks after the initiation of the condition.

Estimating HPV DNA Deposition Between Sexual Partners Using HPV Concordance, Y Chromosome DNA Detection, and Self-reported Sexual Behaviors.

PubMed

Malagón, Talía; Burchell, Ann N; El-Zein, Mariam; Guénoun, Julie; Tellier, Pierre-Paul; Coutlée, François; Franco, Eduardo L

2017-12-05

Detection of human papillomavirus (HPV) DNA in genital samples may not always represent true infections but may be depositions from infected sexual partners. We examined whether sexual risk factors and a biomarker (Y chromosome DNA) were associated with genital HPV partner concordance and estimated the fraction of HPV detections potentially attributable to partner deposition. The HITCH study enrolled young women attending a university or college in Montréal, Canada, and their male partners, from 2005 to 2010. We tested baseline genital samples for Y chromosome DNA and HPV DNA using polymerase chain reaction. Type-specific HPV concordance was 42.4% in partnerships where at least one partner was HPV DNA positive. Y chromosome DNA predicted type-specific HPV concordance in univariate analyses, but in multivariable models the independent predictors of concordance were days since last vaginal sex (26.5% higher concordance 0-1 vs 8-14 days after last vaginal sex) and condom use (22.6% higher concordance in never vs always users). We estimated that 14.1% (95% confidence interval [CI], 6.3-21.9%) of HPV DNA detections in genital samples were attributable to vaginal sex in the past week. A substantial proportion of HPV DNA detections may be depositions due to recent unprotected vaginal sex. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Pathogen Populations Evolve to Greater Race Complexity in Agricultural Systems – Evidence from Analysis of Rhynchosporium secalis Virulence Data

PubMed Central

Zhan, Jiasui; Yang, Lina; Zhu, Wen; Shang, Liping; Newton, Adrian C.

2012-01-01

Fitness cost associated with pathogens carrying unnecessary virulence alleles is the fundamental assumption for preventing the emergence of complex races in plant pathogen populations but this hypothesis has rarely been tested empirically on a temporal and spatial scale which is sufficient to distinguish evolutionary signals from experimental error. We analyzed virulence characteristics of ∼1000 isolates of the barley pathogen Rhynchosporium secalis collected from different parts of the United Kingdom between 1984 and 2005. We found a gradual increase in race complexity over time with a significant correlation between sampling date and race complexity of the pathogen (r20 = 0.71, p = 0.0002) and an average loss of 0.1 avirulence alleles (corresponding to an average gain of 0.1 virulence alleles) each year. We also found a positive and significant correlation between barley cultivar diversity and R. secalis virulence variation. The conditions assumed to favour complex races were not present in the United Kingdom and we hypothesize that the increase in race complexity is attributable to the combination of natural selection and genetic drift. Host resistance selects for corresponding virulence alleles to fixation or dominant frequency. Because of the weak fitness penalty of carrying the unnecessary virulence alleles, genetic drift associated with other evolutionary forces such as hitch-hiking maintains the frequency of the dominant virulence alleles even after the corresponding resistance factors cease to be used. PMID:22723870

NASA's International Space Station: A Testbed for Planetary Protection Protocol Development

NASA Technical Reports Server (NTRS)

Bell, M. S.; Rucker, M.; Love, S.; Johnson, J.; Chambliss, J.; Pierson, D.; Ott, M.; Mary, N.; Glass, B.; Lupisella, M.;

Nasa's International Space Station: A Testbed for Planetary Protection Protocol Development

NASA Technical Reports Server (NTRS)

Bell, M. S.; Rucker, M.; Love, S.; Johnson, J.; Chambliss, J.; Pierson, D.; Ott, M.; Mary, N.; Glass, B.; Lupisella, M.;

Single-surgeon experience with robot-assisted ureteroneocystostomy for distal ureteral pathologies in adults.

PubMed

Lee, Ziho; Sehgal, Shailen; Llukani, Elton; Reilly, Christopher; Doumanian, Leo; Mydlo, Jack; Lee, David Inkoo; Eun, Daniel Dong-In

2013-08-01

To demonstrate our technical approach for robot-assisted ureteroneocystostomy (R-UNC) for benign and malignant distal ureteral pathologies. Between January 2009 and January 2013, a total of 10 patients underwent R-UNC in the distal ureter by a single surgeon. Indications for R-UNC were as follows: idiopathic (3), fistula (2), iatrogenic (2), malignancy (2), and chronic vesicoureteral reflux (1). Tension-free anastomosis was attained in all 10 R-UNC procedures. A psoas hitch was performed in 6/10 cases (60%). Intravesical and extravesical reimplantations were completed in 5/10 (50%) and 5/10 cases (50%), respectively. A nonrefluxing ureter was constructed in 2/10 cases (20%). The patients' mean age was 52.9±16.6 years, their mean body mass index was 30.8±6.3 kg/m(2), the mean operative time was 211.7±69.3 minutes, mean estimated blood loss was 102.5±110.8 mL, and mean length of stay was 2.8±2.3 days. There were no intraoperative complications. There was one Clavien-Dindo grade I and one Clavien-Dindo grade II postoperative complication. The mean postoperative follow-up duration was 28.5±15.5 months. Two patients had recurrence of ureteral strictures at 3 months postoperatively and were managed successfully with balloon dilation. Our technique for R-UNC demonstrates good perioperative outcomes. However, underlying periureteral inflammation and pelvic adhesions may predispose patients for stricture recurrence after R-UNC.

Hydronephrosis Presenting 6 Months After Sacral Colpopexy: Case Report and Literature Review.

PubMed

Weber LeBrun, Emily; Santamaria, Estefania; Moy, Louis

The aim of this study was to describe a case of uterovaginal prolapse managed with robotic-assisted sacral colpopexy complicated by severe right-sided hydronephrosis despite normal intraoperative cystoscopy. A 68-year-old woman presented with a worsening vaginal bulge over the past 2 years. Tricompartment stage 2 uterovaginal prolapse, with dominant cystocele and skin erosion at the posterior fourchette from prolapse friction, was identified on physical examination, and the patient underwent pelvic reconstructive surgery, including sacral colpopexy. The patient was discharged on postoperative day 4 after being treated for a urinary tract infection. At her 6-week postoperative visit, the patient demonstrated normal vaginal support. She presented 6 months postoperatively with right-sided hydronephrosis with an almost imperceptible stricture where the right iliac vessels cross the pelvic brim, demonstrating a delayed manifestation of ureteral injury. She underwent open ureteroscopy, ureteroneocystostomy with vesicopsoas hitch, and ureteral stent placement. Ureteroscopy demonstrated a very mild narrowed caliber of the ureter just above the sacroiliac joint without overt obstruction. Follow-up intravenous pyelogram demonstrated no evidence of damage or obstruction. At nearly 1-year follow-up, the patient remained asymptomatic and had normal renal function. This case demonstrates the challenges of an uncommon, but highly morbid, complication of pelvic reconstructive surgery. Even when adequate visualization of the ureters and delicate ureteral dissection is achieved throughout surgery, occult injuries can still occur. Surgeons should maintain a high index of suspicion of ureteral injury when evaluating patients for late presentations of postoperative complications.

Multiple neural states of representation in short-term memory? It's a matter of attention.

PubMed

Larocque, Joshua J; Lewis-Peacock, Jarrod A; Postle, Bradley R

2014-01-01

Short-term memory (STM) refers to the capacity-limited retention of information over a brief period of time, and working memory (WM) refers to the manipulation and use of that information to guide behavior. In recent years it has become apparent that STM and WM interact and overlap with other cognitive processes, including attention (the selection of a subset of information for further processing) and long-term memory (LTM-the encoding and retention of an effectively unlimited amount of information for a much longer period of time). Broadly speaking, there have been two classes of memory models: systems models, which posit distinct stores for STM and LTM (Atkinson and Shiffrin, 1968; Baddeley and Hitch, 1974); and state-based models, which posit a common store with different activation states corresponding to STM and LTM (Cowan, 1995; McElree, 1996; Oberauer, 2002). In this paper, we will focus on state-based accounts of STM. First, we will consider several theoretical models that postulate, based on considerable behavioral evidence, that information in STM can exist in multiple representational states. We will then consider how neural data from recent studies of STM can inform and constrain these theoretical models. In the process we will highlight the inferential advantage of multivariate, information-based analyses of neuroimaging data (fMRI and electroencephalography (EEG)) over conventional activation-based analysis approaches (Postle, in press). We will conclude by addressing lingering questions regarding the fractionation of STM, highlighting differences between the attention to information vs. the retention of information during brief memory delays.

A manned lunar outpost. Design considerations for three key elements in an initial manned lunar outpost

NASA Technical Reports Server (NTRS)

Bell, Larry; Trotti, Guillermo; Brown, Jeff; Bhattacharya, Nilajan; Moore, Nathan; Polette, Tom; Toups, Larry

1988-01-01

The Initial Manned Lunar Outpost (IMLO) is proposed as the initial permanent base for manned activities on the Moon. The study concentrated on identifying the equipment, support systems, and initial base configuration necessary to accomplish the various science, industrial and exploration activities planned. The primary concepts of the MLO were the use of hard modules for habitation areas creating a flexible, modular transportation system; designing a multi-functional vehicle; and using an overhead radiation protection system. The transportation system, dubbed the Lunar Mobile Surface Transport System (LMSTS), carries the hard modules to the surface of the moon and provides a method to move them to the desired location through the use of interchangeable pallets. The avionics pallets are changed-out with wheel and hitch pallets, transforming the LMSTS into a "tractor trailer" used with the Multi-Functional Vehicle (MFV). The modules are placed under the Regolith Support Structure (RSS) which provides a stable environment and radiation protection for the entire base. The overhead structure was chosen over simply burying the modules to provide a study on the advantages and disadvantages of this type of system. The advantages include easy access to the exterior of the modules, providing a protected area for vehicles and equipment used in EVA, and creating an area of constant temperature. Disadvantages include a need for prefabrication of structural components, including the preconstruction and construction phases of the initial MLO. The design approach taken considered existing and near-term materials and technology only, without the consideration of possible future building technologies.

Hurricane Maria, 2017 Hydrographic Response for Puerto Rico and U.S. Virgin Islands by the NOAA Ship Thomas Jefferson

NASA Astrophysics Data System (ADS)

Gump, D.; Klemm, A.; van Westendorp, C.; Wood, D. A.; Doroba, J.

2017-12-01

After many coastal natural disasters, ports and harbors must be surveyed for navigation dangers, cleared, and opened as quickly as possible to facilitate recovery and reconstruction. The appropriate survey asset to use varies by location and condition. Routinely, hydrographic response to a natural disaster is conducted by survey teams with trailer-hitched vessels deployed quickly by land. This was the case for Hurricanes Harvey, Irma and Nate which struck mainland U.S. In the U.S. territories of Puerto Rico and the Virgin Islands post-Hurricane Maria, however, the devastation to the regional infrastructure resulted in a dearth of adequate accommodations, fuel, security and passable roads required to support a land-based response. On September 24th, 2017, NOAA Ship Thomas Jefferson (TJ), a 208-foot-long hydrographic survey vessel with a 38-person complement and two 28-foot-long survey launches, began an uninterrupted 20-day cruise to survey major ports around the islands. The ship's crew acquired high-resolution multibeam echo sounder (MBES) and concurrent object-detection side scan sonar (SSS) in and around 18 individual port facilities in 13 areas. The TJ is the appropriate platform for sustained remote response due to a self-contained infrastructure that supports deployment and recovery of survey launches, as well as 24/7 data processing facilities. The TJ crew produced digital terrain models and SSS mosaics, in addition to developing new reports on specific hazards overnight. These products quickly informed responders, stakeholders and responsible authorities about the efficacy of waterways.

Integrated Cryogenic Satellite Communications Cross-Link Receiver Experiment

NASA Technical Reports Server (NTRS)

Romanofsky, R. R.; Bhasin, K. B.; Downey, A. N.; Jackson, C. J.; Silver, A. H.; Javadi, H. H. S.

1995-01-01

An experiment has been devised which will validate, in space, a miniature, high-performance receiver. The receiver blends three complementary technologies; high temperature superconductivity (HTS), pseudomorphic high electron mobility transistor (PHEMT) monolithic microwave integrated circuits (MMIC), and a miniature pulse tube cryogenic cooler. Specifically, an HTS band pass filter, InP MMIC low noise amplifier, HTS-sapphire resonator stabilized local oscillator (LO), and a miniature pulse tube cooler will be integrated into a complete 20 GHz receiver downconverter. This cooled downconverter will be interfaced with customized signal processing electronics and integrated onto the space shuttle's 'HitchHiker' carrier. A pseudorandom data sequence will be transmitted to the receiver, which is in low Earth orbit (LEO), via the Advanced Communication Technology Satellite (ACTS) on a 20 GHz carrier. The modulation format is QPSK and the data rate is 2.048 Mbps. The bit error rate (BER) will be measured in situ. The receiver is also equipped with a radiometer mode so that experiment success is not totally contingent upon the BER measurement. In this mode, the receiver uses the Earth and deep space as a hot and cold calibration source, respectively. The experiment closely simulates an actual cross-link scenario. Since the receiver performance depends on channel conditions, its true characteristics would be masked in a terrestrial measurement by atmospheric absorption and background radiation. Furthermore, the receiver's performance depends on its physical temperature, which is a sensitive function of platform environment, thermal design, and cryocooler performance. This empirical data is important for building confidence in the technology.

Endoscope-assisted, minimally invasive evacuation of sub-acute/chronic epidural hematoma: Novelty or paradox of Theseus?

PubMed

Ansari, Ishtyaque; Futane, Sameer; Ansari, Ashfaque

2016-08-01

Sub-acute/chronic epidural hematoma (EDH) may present with nagging symptoms of headache, nausea, vomiting, lethargy, etc. We attempted to offer a minimally invasive, single burr hole, endoscope-assisted evacuation of EDHs instead of a conventional craniotomy. Seven patients with sub-acute/chronic EDH (six supratentorial and one infratentorial) presented to us 3 to 7 days after low-velocity road traffic accidents with complaints of headache and lethargy. The EDH volumes measured between 20 to 50 ml, and the patients were operated on using a single burr hole made through a small incision. We used 0-, 30- and 70-degree, angulated, rigid, high-definition endoscopes to identify and evacuate the organized clots in the extradural space. Flexible catheters were used for suction and irrigation. After achieving hemostasis, the dura was hitched back to the burr hole site. The wound was closed over a negative suction drain. All patients had prompt recovery from symptoms. Postoperative CT scans showed complete or near complete evacuation of the hematomas. The hospital stay and analgesic requirements were minimal. There was no infective complication or conversion to conventional open surgery. The average time for surgery was 77.8 min, and average blood loss was 328.5 ml. Endoscope-assisted evacuation of sub-acute/chronic EDH is a novel concept, which offers quick relief from symptoms in a minimally invasive fashion and a cosmetically acceptable way. None of the standard principles of surgery are hampered. It avoids extensive dissection of the temporalis or sub-occipital muscles. However, achieving hemostasis can be difficult. Further study and better equipment will validate the procedure.

The return of infectious disease.

PubMed

Garrett, L

1996-11-01

This article presents the history of efforts to control the spread of infectious disease from the post-antibiotic era to 1995. Since World War II, public health strategy has focused on the eradication of microbes using powerful medical weaponry. The goal was to push humanity through a ¿health transition,¿ leaving the age of infectious disease permanently behind. But recent developments have shown that this grandiose optimism was premature. As people move across international borders, unwanted microbial hitch-hikers tag along, as happened in the case of Ebola. In large cities, sex industries arise and multiple-partner sex becomes more common, prompting rapid increases in sexually transmitted disease. Moreover, the practice of sharing syringes is a ready vehicle for the transmission of microbes while unhygienic health facilities become centers for the dissemination of disease rather than its control. Black market access to antimicrobials has led to overuse or outright misuse of the drugs and the emergence of resistant bacteria and parasites. Consequently, old organisms, aided by mankind's misuse of disinfectants and drugs, may take on new and more lethal forms. Even when allegations of biological warfare are not flying, it is often difficult to obtain accurate information about outbreaks of disease, particularly in countries dependent on foreign investment or tourism or both. Unfortunately, only 6 laboratories in the world meet security and safety standards that would make them suitable sites for research on the world's deadliest microbes. National security warrants bolder steps involving focusing not only on microbes directly dangerous to humans, but also on those that could pose major threats to crops or livestock. Unfortunately, economic crises have led to budget cuts, particularly in health care, at all levels of government in the US.

Cryopreservation of Embryos of the Mediterranean Fruit Fly Ceratitis capitata Vienna 8 Genetic Sexing Strain

PubMed Central

Augustinos, Antonios A.; Rajamohan, Arun; Kyritsis, Georgios A.; Zacharopoulou, Antigone; Haq, Ihsan ul; Targovska, Asya; Caceres, Carlos; Bourtzis, Kostas; Abd-Alla, Adly M. M.

2016-01-01

The Mediterranean fruit fly, Ceratitis capitata, is one of the most serious pests of fruit crops world-wide. During the last decades, area-wide pest management (AW-IPM) approaches with a sterile insect technique (SIT) component have been used to control populations of this pest in an effective and environment-friendly manner. The development of genetic sexing strains (GSS), such as the Vienna 8 strain, has been played a major role in increasing the efficacy and reducing the cost of SIT programs. However, mass rearing, extensive inbreeding, possible bottleneck phenomena and hitch-hiking effects might pose major risks for deterioration and loss of important genetic characteristics of domesticated insect. In the present study, we present a modified procedure to cryopreserve the embryos of the medfly Vienna 8 GSS based on vitrification and used this strain as insect model to assess the impact of the cryopreservation process on the genetic structure of the cryopreserved insects. Forty-eight hours old embryos, incubated at 24°C, were found to be the most suitable developmental stage for cryopreservation treatment for high production of acceptable hatch rate (38%). Our data suggest the absence of any negative impact of the cryopreservation process on egg hatch rate, pupation rates, adult emergence rates and stability of the temperature sensitive lethal (tsl) character on two established cryopreserved lines (flies emerged from cryopreserved embryos), named V8-118 and V8-228. Taken together, our study provides an optimized procedure to cryopreserve the medfly Vienna 8 GSS and documents the absence of any negative impact on the genetic structure and quality of the strain. Benefits and sceneries for utilization of this technology to support operational SIT projects are discussed in this paper. PMID:27537351

Encoding: the keystone to efficient functioning of verbal short-term memory.

PubMed

Barry, Johanna G; Sabisch, Beate; Friederici, Angela D; Brauer, Jens

2011-11-01

Verbal short-term memory (VSTM) is thought to play a critical role in language learning. It is indexed by the nonword repetition task where listeners are asked to repeat meaningless words like 'blonterstaping'. The present study investigated the effect on nonword repetition performance of differences in efficiency of functioning of some part of the neural architecture mediating VSTM. Hypotheses were stated within Baddeley and Hitch's (1974) multicomponent model of VSTM, with respect to regions of the brain known to be active during tasks tapping into VSTM. We were specifically interested in activations associated with the posterior planum temporale (Spt) which emerge during rehearsal since this region is hypothesized to be central to VTSM (Buchsbaum, Olsen, Koch, & Berman, 2005a). Participants performed a delayed reaction time task in the scanner which explicitly mimicked the three main stages of information-processing involved in VSTM (encoding, rehearsal, recall (here recognition)). The data for each stage were then convolved with scores from a separately measured nonword repetition task. Rather than observing a pattern of individual differences located to specific regions specialized for supporting VSTM, a dissociation in direction of correlation in overlapping regions of the brain was observed during encoding and recognition. Larger hemodynamic responses during encoding were associated with better nonword repetition, and vice versa during recognition. There was little evidence for a network of activations specialized for VSTM. Instead, the main correlations were observed in regions also known to be involved in long-term memory. It seems that individuals who are better at nonword repetition and hence at language learning, activate these regions more efficiently than poorer nonword-repeaters early after stimulus input. These observations are discussed with respect to various models proposed for explaining the phenomenon of VSTM. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Cryopreservation of Embryos of the Mediterranean Fruit Fly Ceratitis capitata Vienna 8 Genetic Sexing Strain.

PubMed

Augustinos, Antonios A; Rajamohan, Arun; Kyritsis, Georgios A; Zacharopoulou, Antigone; Haq, Ihsan Ul; Targovska, Asya; Caceres, Carlos; Bourtzis, Kostas; Abd-Alla, Adly M M

2016-01-01

The Mediterranean fruit fly, Ceratitis capitata, is one of the most serious pests of fruit crops world-wide. During the last decades, area-wide pest management (AW-IPM) approaches with a sterile insect technique (SIT) component have been used to control populations of this pest in an effective and environment-friendly manner. The development of genetic sexing strains (GSS), such as the Vienna 8 strain, has been played a major role in increasing the efficacy and reducing the cost of SIT programs. However, mass rearing, extensive inbreeding, possible bottleneck phenomena and hitch-hiking effects might pose major risks for deterioration and loss of important genetic characteristics of domesticated insect. In the present study, we present a modified procedure to cryopreserve the embryos of the medfly Vienna 8 GSS based on vitrification and used this strain as insect model to assess the impact of the cryopreservation process on the genetic structure of the cryopreserved insects. Forty-eight hours old embryos, incubated at 24°C, were found to be the most suitable developmental stage for cryopreservation treatment for high production of acceptable hatch rate (38%). Our data suggest the absence of any negative impact of the cryopreservation process on egg hatch rate, pupation rates, adult emergence rates and stability of the temperature sensitive lethal (tsl) character on two established cryopreserved lines (flies emerged from cryopreserved embryos), named V8-118 and V8-228. Taken together, our study provides an optimized procedure to cryopreserve the medfly Vienna 8 GSS and documents the absence of any negative impact on the genetic structure and quality of the strain. Benefits and sceneries for utilization of this technology to support operational SIT projects are discussed in this paper.

Independent evolution of the core and accessory gene sets in the genus Neisseria: insights gained from the genome of Neisseria lactamica isolate 020-06

PubMed Central

2010-01-01

Background The genus Neisseria contains two important yet very different pathogens, N. meningitidis and N. gonorrhoeae, in addition to non-pathogenic species, of which N. lactamica is the best characterized. Genomic comparisons of these three bacteria will provide insights into the mechanisms and evolution of pathogenesis in this group of organisms, which are applicable to understanding these processes more generally. Results Non-pathogenic N. lactamica exhibits very similar population structure and levels of diversity to the meningococcus, whilst gonococci are essentially recent descendents of a single clone. All three species share a common core gene set estimated to comprise around 1190 CDSs, corresponding to about 60% of the genome. However, some of the nucleotide sequence diversity within this core genome is particular to each group, indicating that cross-species recombination is rare in this shared core gene set. Other than the meningococcal cps region, which encodes the polysaccharide capsule, relatively few members of the large accessory gene pool are exclusive to one species group, and cross-species recombination within this accessory genome is frequent. Conclusion The three Neisseria species groups represent coherent biological and genetic groupings which appear to be maintained by low rates of inter-species horizontal genetic exchange within the core genome. There is extensive evidence for exchange among positively selected genes and the accessory genome and some evidence of hitch-hiking of housekeeping genes with other loci. It is not possible to define a 'pathogenome' for this group of organisms and the disease causing phenotypes are therefore likely to be complex, polygenic, and different among the various disease-associated phenotypes observed. PMID:21092259

Characterize Human Forward Contamination Project

NASA Technical Reports Server (NTRS)

Rucker, Michelle

2015-01-01

Let's face it: wherever we go, we will inevitably carry along the little critters that live in and on us. Conventional wisdom has long held that it's unlikely those critters could survive the space environment, but in 2007 microscopic animals called Tardigrades survived exposure to space and in 2008 Cyanobacteria lived for 548 days outside the International Space Station (ISS). But what about the organisms we might reasonably expect a crewed spacecraft to leak or vent? Do we even know what they are? How long might our tiny hitch-hikers survive in close proximity to a warm spacecraft that periodically leaks/vents water or oxygen-and how might they mutate with long-duration exposure? Unlike the Mars rovers that we cleaned once and sent on their way, crew members will provide a constantly regenerating contaminant source. Are we prepared to certify that we can meet forward contamination protocols as we search for life at new destinations? This project has four technical objectives: 1. TEST: Develop a test plan to leverage existing equipment (i.e. ISS) to characterize the kinds of organisms we can reasonably expect pressurized, crewed volumes to vent or leak overboard; 2. ANALYSIS: Develop an analysis plan to study those organisms in relevant destination environments, including spacecraft-induced conditions; 3. MODEL: Develop a modeling plan to model organism transport mechanisms in relevant destination environments; 4. SHARE: Develop a plan to disseminate findings and integrate recommendations into exploration requirements & ops. In short, we propose a system engineering approach to roadmap the necessary experiments, analysis, and modeling up front--rather than try to knit together disparate chunks of data into a sensible conclusion after the fact.

Building Better Biosensors for Exploration into Deep-Space, Using Humanized Yeast

NASA Technical Reports Server (NTRS)

Liddell, Lauren; Santa Maria, Sergio; Tieze, Sofia; Bhattacharya, Sharmila

2017-01-01

1.BioSentinel is 1 of 13 secondary payloads hitching a ride beyond Low Earth Orbit on Exploration Mission 1 (EM-1), set to launch from NASAs Space Launch System in 2019. EM-1 is our first opportunity to investigate the effects of the deep space environment on a eukaryotic biological system, the budding yeast S. cerevisiae. Though separated by a billion years of evolution we share hundreds of genes important for basic cell function, including responses to DNA damage. Thus, yeast is an ideal biosensor for detecting typesextent of damage induced by deep-space radiation.We will fly desiccated cells, then rehydrate to wake them up when the automated payload is ready to initiate the experiment. Rehydration solution contains SC (Synthetic Complete) media and alamarBlue, an indicator for changes in growth and metabolism. Telemetry of LED readings will then allow us to detect how cells respond throughout the mission. The desiccation-rehydration process can be extremely damaging to cells, and can severely diminish our ability to accurately measure and model cellular responses to deep-space radiation. The aim of this study is to develop a better biosensor: yeast strains that are more resistant to desiccation stress. We will over-express known cellular protectants, including hydrophilin Sip18, the protein disaggregase Hsp104, and thioredoxin Trx2, a responder to oxidative stress, then measure cell viability after desiccation to determine which factors improve stress tolerance. Over-expression of SIP18 in wine yeast starter cultures was previously reported to increase viability following desiccation stress by up to 70. Thus, we expect similar improvements in our space-yeast strains. By designing better yeast biosensors we can better prepare for and mitigate the potential dangers of deep-space radiation for future missions.This work is funded by NASAs AES program.

Mitochondrial DNA haplogroup D4a is a marker for extreme longevity in Japan.

PubMed

Bilal, Erhan; Rabadan, Raul; Alexe, Gabriela; Fuku, Noriyuki; Ueno, Hitomi; Nishigaki, Yutaka; Fujita, Yasunori; Ito, Masafumi; Arai, Yasumichi; Hirose, Nobuyoshi; Ruckenstein, Andrei; Bhanot, Gyan; Tanaka, Masashi

2008-06-11

We report results from the analysis of complete mitochondrial DNA (mtDNA) sequences from 112 Japanese semi-supercentenarians (aged above 105 years) combined with previously published data from 96 patients in each of three non-disease phenotypes: centenarians (99-105 years of age), healthy non-obese males, obese young males and four disease phenotypes, diabetics with and without angiopathy, and Alzheimer's and Parkinson's disease patients. We analyze the correlation between mitochondrial polymorphisms and the longevity phenotype using two different methods. We first use an exhaustive algorithm to identify all maximal patterns of polymorphisms shared by at least five individuals and define a significance score for enrichment of the patterns in each phenotype relative to healthy normals. Our study confirms the correlations observed in a previous study showing enrichment of a hierarchy of haplogroups in the D clade for longevity. For the extreme longevity phenotype we see a single statistically significant signal: a progressive enrichment of certain "beneficial" patterns in centenarians and semi-supercentenarians in the D4a haplogroup. We then use Principal Component Spectral Analysis of the SNP-SNP Covariance Matrix to compare the measured eigenvalues to a Null distribution of eigenvalues on Gaussian datasets to determine whether the correlations in the data (due to longevity) arises from some property of the mutations themselves or whether they are due to population structure. The conclusion is that the correlations are entirely due to population structure (phylogenetic tree). We find no signal for a functional mtDNA SNP correlated with longevity. The fact that the correlations are from the population structure suggests that hitch-hiking on autosomal events is a possible explanation for the observed correlations.

Mitochondrial DNA Haplogroup D4a Is a Marker for Extreme Longevity in Japan

PubMed Central

Bilal, Erhan; Rabadan, Raul; Alexe, Gabriela; Fuku, Noriyuki; Ueno, Hitomi; Nishigaki, Yutaka; Fujita, Yasunori; Ito, Masafumi; Arai, Yasumichi; Hirose, Nobuyoshi; Ruckenstein, Andrei; Bhanot, Gyan; Tanaka, Masashi

2008-01-01

We report results from the analysis of complete mitochondrial DNA (mtDNA) sequences from 112 Japanese semi-supercentenarians (aged above 105 years) combined with previously published data from 96 patients in each of three non-disease phenotypes: centenarians (99–105 years of age), healthy non-obese males, obese young males and four disease phenotypes, diabetics with and without angiopathy, and Alzheimer's and Parkinson's disease patients. We analyze the correlation between mitochondrial polymorphisms and the longevity phenotype using two different methods. We first use an exhaustive algorithm to identify all maximal patterns of polymorphisms shared by at least five individuals and define a significance score for enrichment of the patterns in each phenotype relative to healthy normals. Our study confirms the correlations observed in a previous study showing enrichment of a hierarchy of haplogroups in the D clade for longevity. For the extreme longevity phenotype we see a single statistically significant signal: a progressive enrichment of certain “beneficial” patterns in centenarians and semi-supercentenarians in the D4a haplogroup. We then use Principal Component Spectral Analysis of the SNP-SNP Covariance Matrix to compare the measured eigenvalues to a Null distribution of eigenvalues on Gaussian datasets to determine whether the correlations in the data (due to longevity) arises from some property of the mutations themselves or whether they are due to population structure. The conclusion is that the correlations are entirely due to population structure (phylogenetic tree). We find no signal for a functional mtDNA SNP correlated with longevity. The fact that the correlations are from the population structure suggests that hitch-hiking on autosomal events is a possible explanation for the observed correlations. PMID:18545700

An Fe-S cluster in the conserved Cys-rich region in the catalytic subunit of FAD-dependent dehydrogenase complexes.

PubMed

Shiota, Masaki; Yamazaki, Tomohiko; Yoshimatsu, Keiichi; Kojima, Katsuhiro; Tsugawa, Wakako; Ferri, Stefano; Sode, Koji

2016-12-01

Several bacterial flavin adenine dinucleotide (FAD)-harboring dehydrogenase complexes comprise three distinct subunits: a catalytic subunit with FAD, a cytochrome c subunit containing three hemes, and a small subunit. Owing to the cytochrome c subunit, these dehydrogenase complexes have the potential to transfer electrons directly to an electrode. Despite various electrochemical applications and engineering studies of FAD-dependent dehydrogenase complexes, the intra/inter-molecular electron transfer pathway has not yet been revealed. In this study, we focused on the conserved Cys-rich region in the catalytic subunits using the catalytic subunit of FAD dependent glucose dehydrogenase complex (FADGDH) as a model, and site-directed mutagenesis and electron paramagnetic resonance (EPR) were performed. By co-expressing a hitch-hiker protein (γ-subunit) and a catalytic subunit (α-subunit), FADGDH γα complexes were prepared, and the properties of the catalytic subunit of both wild type and mutant FADGDHs were investigated. Substitution of the conserved Cys residues with Ser resulted in the loss of dye-mediated glucose dehydrogenase activity. ICP-AEM and EPR analyses of the wild-type FADGDH catalytic subunit revealed the presence of a 3Fe-4S-type iron-sulfur cluster, whereas none of the Ser-substituted mutants showed the EPR spectrum characteristic for this cluster. The results suggested that three Cys residues in the Cys-rich region constitute an iron-sulfur cluster that may play an important role in the electron transfer from FAD (intra-molecular) to the multi-heme cytochrome c subunit (inter-molecular) electron transfer pathway. These features appear to be conserved in the other three-subunit dehydrogenases having an FAD cofactor. Copyright © 2016 Elsevier B.V. All rights reserved.

Recessively inherited multiple epiphyseal dysplasia with normal stature, club foot, and double layered patella caused by a DTDST mutation

PubMed Central

Superti-Furga, A.; Neumann, L.; Riebel, T.; Eich, G.; Steinmann, B.; Spranger, J.; Kunze, J.

1999-01-01

We have observed over 25 different mutations in the diastrophic dysplasia sulphate transporter gene (DTDST) in association with the recessive disorders achondrogenesis 1B, atelosteogenesis 2, and diastrophic dysplasia. The c862t (R279W) transition is the most common mutation in non-Finnish patients, but in these disorders it is usually combined with other DTDST mutations. We had not seen a case of homozygosity for c862t (R279W) until we analysed DNA from a 36 year old male with tall-normal stature (180 cm) who asked for genetic counselling for suspected multiple epiphyseal dysplasia. He was treated for club foot and hip dysplasia at birth. Skeletal changes consistent with multiple epiphyseal dysplasia, with the peculiar finding of a double layered patella, were recognised during childhood. Cleft palate, swelling of the ear pinna, and hitch hiker thumb were absent. He was found to be homozygous, and both healthy parents heterozygous, for the R279W mutation in DTDST, and his fibroblasts showed a sulphate incorporation defect typical of DTDST disorders. Counselling was given for a recessive disorder, thereby considerably reducing the probability of affected offspring.
  Multiple epiphyseal dysplasia is more frequently caused by dominant mutations in the COMP (EDM1, McKusick 132400) and COL9A2 genes (EDM2, McKusick 600204). A few other patients and families with features similar to our proband have been described previously and considered to have autosomal recessive MED (EDM4, McKusick 226900). This observation confirms the existence of this entity and assigns it to the phenotypic spectrum associated with mutations at the DTDST locus.


Keywords: multiple epiphyseal dysplasia; DTDST; double layered patella PMID:10465113

Passive Capture Joint with Three Degrees of Freedom

NASA Technical Reports Server (NTRS)

Cloyd, Richard A. (Inventor); Weddendorf, Bruce (Inventor)

2001-01-01

A passive capture joint with three degrees of freedom is presented wherein two structural elements are joined together solely by moving the two elements into position, and which when joined together have rotation in all three axes. The inventive apparatus is comprised of two halves: (1) a joint ball mounted on a stem as in a common trailer hitch, and; (2) a socket. The socket consists of a base having an exterior wall and forming an interior chamber, the chamber having a top end and a bottom end, and an interior wall. The chamber is open at the top end, and forms a spherical cup at the bottom end. The socket base's interior chamber is sized to accept the joint ball. The base also forms at least one bore at an acute angle away from the interior chamber's open end. The bores have a first opening in the interior wall of the chamber, and a second opening in the exterior wall of the base. Retaining balls sized to fit within the bores, but to only partially pass through the first opening, are moveably housed within the bores. The retaining balls are moveably held in the first opening by a compression spring housed in the bore. As the joint ball is inserted in the chamber it forces the retaining balls back into the bore until the equator of the joint ball passes. Because the bore is at an acute angle to the chamber the joint ball cannot exit the chamber without the joint being unlocked. The joint is unlocked by rotating a locking ring which encircles the base and covers the second opening. The locking ring has a radial slot for each retaining ball, disposed angularly from the base, and sized to allow passage of the retaining ball in the radial direction when the locking ring is rotated to align the radial slot with the second opening.

[Rubber band ligation in treatment of hemorrhoids: our experience].

PubMed

Gaj, F; Biviano, I; Sportelli, G; Candeloro, L

2015-01-01

Hemorrhoids are a very common condition. The treatment depends upon persistence and severity of symptoms. For hemorrhoids of II and III grade the rubber band ligation may be therapeutic. Our aim is to report the outcomes of rubber band ligation of hemorrhoids, with a follow up of 6 months. A total of 50 patients underwent rubber band ligation for symptomatic hemorrhoids (grade II and III) without prolapse, between June 2012 and June 2014. All patients underwent plug test to rule out presence of rectal mucosal prolapse and were classified according to PATE classification (1). Each hemorrhoid was ligated with one rubber band through a ligator. All patients were evaluated immediately at the end of the procedure, after ten days and six months after the treatment. Patient's demographic and operative data were collected and analyzed. The mean patients age was 47.6±12.3 years (range 24-72). All procedures were performed without complications. Before rubber band ligation, 42 patients had rectal bleeding, 38 had perineal discomfort and 27 had itching. Ten days after the treatment, 12 patients presented self-limited rectal bleeding, but 10 of these had more hemorrhoids and underwent a second rubber band ligation. No patients complained perineal discomfort, and 8 patients had itching; 78% and 16% of patients respectively, experienced feeling of a foreign body inside the canal anal and anal pain. After 6 months, only 13 patients were occasionally symptomatic: 4 patients had rectal bleeding, 2 had perineal discomfort and 4 had itching. Three more patients presented both perineal discomfort and hitching. None had the feeling of a foreign body in anal canal or anal pain. Rubber band ligation is an efficacious, cost-effective and simple treatment for the second and third degree hemorrhoids without rectal mucosal prolapsed. In our hands, no severe complications developed and minor complications could be handled with ease.

[Reconstruction of the extensor pollicis longus tendon by transposition of the extensor indicis tendon].

PubMed

Loos, A; Kalb, K; Van Schoonhoven, J; Landsleitner Dagger, B

2003-12-01

Rupture of the extensor pollicis longus-tendon (EPL) is a frequent complication after distal radius fractures. Other traumatic and non-traumatic reasons for this tendon lesion are known, including a theory about a disorder in the blood supply to the tendon itself. We examined 40 patients after reconstruction of the EPL-tendon in a mean follow-up time of 30 months. All patients were clinically examined and a DASH questionnaire was answered by all patients. The method to reconstruct the EPL-tendon was the transposition of the extensor indicis-tendon. After the operations the thumb was put in a splint for four weeks in a "hitch-hiker's-position". 31 ruptures of the tendon (77.5 %) were a result of trauma. In 20 of them (50 %) a distal radius fracture had occurred. Clinical examination included measurements of the movement of the thumb- and index-finger joints, the grip strength and the maximal span of the hand. Significant differences were not found. The isolated extension of the index finger was possible in all patients. But it was reduced in ten cases which represent 25 %. Our results were evaluated by the Geldmacher score to evaluate the reconstruction of the EPL-tendon. 20 % excellent, 65 % good, 12.5 % fair and 2.5 % poor results were reached. The Geldmacher score was used critically. We suggest its modification for the evaluation of thumb abduction. The DASH score reached a functional value of ten points which represents a very good result. In conclusion the extensor indicis-transposition is a safe method to reconstruct the EPL-tendon. Its substantial advantage is taking a healthy muscle as the motor, thereby avoiding the risk of using a degenerated muscle in late tendon reconstruction. A powerful extension of the index finger will be maintained by physical education. Generally, the loss of the extension of the index finger is negligible. It does not disturb the patients. But it has to be discussed with the patient before the operation.

The Terrestrial Planets - Edutainment and Science for Grades 7-9

NASA Astrophysics Data System (ADS)

Sornig, Manuela; Sonnabend, Guido; Pietsch-Lindt, Ursula; Stupar, Dusan; Morath, Frank; Bischoff, Sonja; Weiler, Sven

2010-05-01

Over the last years, public outreach has become an integral part of scientific work. In order to motivate the next generation of scientist and in cooperation with the JuniorUniversity program of the University of Cologne and the Cologne Science Adventure "Odysseum" we at the I. Physikalisches Institut developed a concept to introduce our up-to-date scientific work to teenagers between 13 and 15 years of age. The main idea was to motivate adolescents, to provide a cheerful contact with science and the local university, and to have fun. The focus of our scientific work are wind measurements in the upper atmospheres of Mars and Venus by high resolution infrared spectroscopy. The main concept of these observations is quite simple, just involving spectroscopic measurements of light and the well-known Doppler effect. This observational concept as well as general information on the planets were transported during one day consisting of various events. The morning was organized by the Odysseum. Two instructional workshops ("Venus, Earth, Mars", "Mission to Mars") with high "fun-factor" were offered providing an appropriate environment for the children and easy access to the subject. Basic information about the planets Mars and Venus was conveyed as well as some aspects on possible space missions to these planets. Based on that information the children visited our institute in the afternoon where two workshops with hands-on experiments provided deeper inside to the technique of spectroscopy ("Information from the Universe") and the problems of conducting astronomical observations ("Hitch-hiking through the universe"). The latter was also used to introduce the basic methods of how to write a scientific proposal for telescope observing time. Finally, to round up the day and to increase our targeted audience, parents and friends where invited to attend a presentation of the results of the day given by the participants as well as a brief introduction into our scientific work on investigations of dynamical properties on Mars and Venus expanding the knowledge gathered during the day.

A tough egg to crack: recreational boats as vectors for invasive goby eggs and transdisciplinary management approaches.

PubMed

Hirsch, Philipp E; Adrian-Kalchhauser, Irene; Flämig, Sylvie; N'Guyen, Anouk; Defila, Rico; Di Giulio, Antonietta; Burkhardt-Holm, Patricia

2016-02-01

Non-native invasive species are a major threat to biodiversity, especially in freshwater ecosystems. Freshwater ecosystems are naturally rather isolated from one another. Nonetheless, invasive species often spread rapidly across water sheds. This spread is to a large extent realized by human activities that provide vectors. For example, recreational boats can carry invasive species propagules as "aquatic hitch-hikers" within and across water sheds. We used invasive gobies in Switzerland as a case study to test the plausibility that recreational boats can serve as vectors for invasive fish and that fish eggs can serve as propagules. We found that the peak season of boat movements across Switzerland and the goby spawning season overlap temporally. It is thus plausible that goby eggs attached to boats, anchors, or gear may be transported across watersheds. In experimental trials, we found that goby eggs show resistance to physical removal (90 mN attachment strength of individual eggs) and stay attached if exposed to rapid water flow (2.8 m·s(-1)for 1 h). When exposing the eggs to air, we found that hatching success remained high (>95%) even after eggs had been out of water for up to 24 h. It is thus plausible that eggs survive pick up, within-water and overland transport by boats. We complemented the experimental plausibility tests with a survey on how decision makers from inside and outside academia rate the feasibility of managing recreational boats as vectors. We found consensus that an installation of a preventive boat vector management is considered an effective and urgent measure. This study advances our understanding of the potential of recreational boats to serve as vectors for invasive vertebrate species and demonstrates that preventive management of recreational boats is considered feasible by relevant decision makers inside and outside academia.

Walk or ride? Phoretic behaviour of amblyceran and ischnoceran lice.

PubMed

Bartlow, Andrew W; Villa, Scott M; Thompson, Michael W; Bush, Sarah E

2016-04-01

Phoresy is a behaviour where one organism hitches a ride on another more mobile organism. This is a common dispersal mechanism amongst relatively immobile species that specialise on patchy resources. Parasites specialise on patchily distributed resources: their hosts. Although host individuals are isolated in space and time, parasites must transmit between hosts or they will die with their hosts. Lice are permanent obligate ectoparasites that complete their entire life cycle on their host. They typically transmit when hosts come into direct contact; however, lice are also capable of transmitting phoretically. Yet, phoresy is rare amongst some groups of lice. Fundamental morphological differences have traditionally been used to explain the phoretic differences amongst different suborders of lice; however, these hypotheses do not fully explain observed patterns. We propose that a more fundamental natural history trait may better explain variation in phoresy. Species able to disperse under their own power should be less likely to engage in phoresy than more immobile species. Here we experimentally tested the relationship between independent louse mobility and phoresy using a system with four species of lice (Phthiraptera: Ischnocera and Amblycera) that all parasitize a single host species, the Rock Pigeon (Columba livia). We quantified the relative ability of all four species of lice to move independently off the host, and we quantified their ability to attach to, and remain attached to, hippoboscid flies (Pseudolynchia canariensis). Our results show that the most mobile louse species is the least phoretic, and the most phoretic species is quite immobile off the host. Our findings were consistent with the hypothesis that phoretic dispersal should be rare amongst species of lice that are capable of independent dispersal; however other factors such as interspecific competition may also play a role. Copyright © 2016 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Characterize Human Forward Contamination Project

NASA Technical Reports Server (NTRS)

Rucker, Michelle

2015-01-01

Let's face it: wherever we go, we will inevitably carry along the little critters that live in and on us. Conventional wisdom has long held that it's unlikely those critters could survive the space environment, but in 2007 microscopic animals called Tardigrades survived exposure to space and in 2008 Cyanobacteria lived for 548 days outside the International Space Station (ISS). But what about the organisms we might reasonably expect a crewed spacecraft to leak or vent? Do we even know what they are? How long might our tiny hitch-hikers survive in close proximity to a warm spacecraft that periodically leaks/vents water or oxygen-and how might they mutate with long-duration exposure? Unlike the Mars rovers that we cleaned once and sent on their way, crew members will provide a constantly regenerating contaminant source. Are we prepared to certify that we can meet forward contamination protocols as we search for life at new destinations? This project has four technical objectives: 1. TEST: Develop a test plan to leverage existing equipment (i.e. ISS) to characterize the kinds of organisms we can reasonably expect pressurized, crewed volumes to vent or leak overboard; as part of testing, we'll need to develop an Extravehicular Activity (EVA)-compatible tool that can withstand the pressure and temperature extremes of space, as well as collect, separate, and store multiple samples; 2. ANALYSIS: Develop an analysis plan to study those organisms in relevant destination environments, including spacecraft-induced conditions; 3. MODEL: Develop a modeling plan to model organism transport mechanisms in relevant destination environments; 4. SHARE: Develop a plan to disseminate findings and integrate recommendations into exploration requirements & ops. In short, we propose a system engineering approach to roadmap the necessary experiments, analysis, and modeling up front--rather than try to knit together disparate chunks of data into a sensible conclusion after the fact.

Modeling of traction-coupling properties of wheel propulsor

NASA Astrophysics Data System (ADS)

Sakhapov, R. L.; Nikolaeva, R. V.; Gatiyatullin, M. H.; Makhmutov, M. M.

2017-12-01

In conditions of operation of aggregates on soils with low bearing capacity, the main performance indicators of their operation are determined by the properties of retaining the functional qualities of the propulsor. Therefore, the parameters of the anti-skid device can not be calculated by only one criterion. The equipment of propellers with anti-skid devices, which allow to reduce the compaction effect of the propulsion device on the soil, seems to be a rational solution to the problem of increasing traction and coupling properties of the driving wheels. The mathematical model is based on the study of the interaction of the driving wheel with anti-skid devices and a deformable bearing surface, which takes into account the wheel diameter, skid coefficient, the parameters of the anti-skid device, the physical and mechanical properties of the soil. As a basic mathematical model that determines the dependence of the coupling properties on the wheel parameters, the model obtained as a result of integration and reflecting the process of soil deformation from the shear stress is adopted. The total value of the resistance forces will determine the force of the hitch pressure on the horizontal soil layers, and the value of its deformation is the degree of wheel slippage. When the anti-skid devices interact with the soil, the traction capacity of the wheel is composed of shear forces, soil shear and soil deformation forces with detachable hooks. As a result of the interaction of the hook with the soil, the latter presses against the walls of the hook with the force equal to the sum of the hook load and the resistance to movement. During operation, the linear dimensions of the hook will decrease, which is not taken into account by the safety factor. Abrasive wear of the thickness of the hook is approximately proportional to the work of friction caused by the movement of the hook when inserted into the soil and slipping the wheel.

Effect of ventriculectomy versus ventriculocordectomy on upper airway noise in draught horses with recurrent laryngeal neuropathy.

PubMed

Cramp, P; Derksen, F J; Stick, J A; Nickels, F A; Brown, K E; Robinson, P; Robinson, N E

2009-11-01

Little is known about the efficacy of bilateral ventriculectomy (VE) or bilateral ventriculocordectomy (VCE) in draught horses. To compare the effect of VE and VCE on upper airway noise in draught horses with recurrent laryngeal neuropathy (RLN) by use of quantitative sound analysis techniques. In competitive draught horses with grade 4 RLN, VE and VCE reduce upper airway noise during exercise, but VCE is more effective. Thirty competitive hitch or pulling draught horses with grade 4 RLN were evaluated for upper airway sound during exercise. Respiratory rate (RR), inspiratory (Ti) and expiratory time (Te), the ratio between Ti and Te (Ti/Te), inspiratory (Sli) and expiratory sound levels (Sle), the ratio between Sli and Sle (Sli/Sle), and peak sound intensity of the second formant (F2) were calculated. Eleven horses were treated with VE and 19 with VCE. After 90 days of voice and physical rest and 30 days of work, the horses returned for post operative upper airway sound evaluation and resting videoendoscopy. VE significantly reduced Ti/Te, Sli, Sli/Sle and the sound intensity of F2. Respiratory rate, Ti, Te and Sle were unaffected by VE. VCE significantly reduced Ti/Te, Ti, Te, Sli, Sli/Sle and the sound intensity of F2, while RR and Sle were unaffected. The reduction in sound intensity of F2 following VCE was significantly greater than following VE. After VE and VCE, 7/11 (64%) and 15/18 (83%) owners, respectively, concluded that the surgery improved upper airway sound in their horses sufficiently for successful competition. VE and VCE significantly reduce upper airway noise and indices of airway obstruction in draught horses with RLN, but VCE is more effective than VE. The procedures have few post operative complications. VCE is recommended as the preferred treatment for RLN in draught horses. Further studies are required to evaluate the longevity of the procedure's results.

A key to success: optimizing the planning process

NASA Astrophysics Data System (ADS)

Turk, Huseyin; Karakaya, Kamil

2014-05-01

By adopting The NATO Strategic Concept Document in 2010, some important changes in the perception of threat and management of crisis were introduced. This new concept, named ''Comprehensive Approach'', includes the precautions of pre-crisis management, applications of crisis-duration management and reconstruction phase of post-intervention management. NATO will be interested in not only the political and military options , but also social, economical and informational aspects of crisis. NATO will take place in all phases of conflict. The conflicts which occur outside the borders of NATO's nations and terrorism are perceived as threat sources for peace and stability. In addition to conventional threats, cyber attacks which threaten network-supported communication systems, preventing applications from accessing to space that will be used in different fields of life. On the other hand, electronic warfare capabilities which can effect us negatively are added to threat list as new threats. In the process in which military is thought as option, a harder planning phase is waiting for NATO's decision makers who struggle for keeping peace and security. Operation planning process which depends on comprehensive approach, contains these steps: Situational awareness of battlefield, evaluation of the military intervention options, orientation, developing an operation plan, reviewing the plan and transition phases.1 To be successful in theater which is always changing with the technological advances, there has to be an accurate and timely planning on the table. So, spending time for planning can be shown as one of the biggest problem. In addition, sustaining situational awareness which is important for the whole operation planning process, technical command and control hitches, human factor, inability to determine the center of gravity of opponent in asymmetrical threat situations can be described as some of the difficulties in operation planning. In this study, a possible air operation planning process is analyzed according to a comprehensive approach. The difficulties of planning are identified. Consequently, for optimizing a decisionmaking process of an air operation, a planning process is identified in a virtual command and control structure.

Objective Assessment of Knot-Tying Proficiency With the Fundamentals of Arthroscopic Surgery Training Program Workstation and Knot Tester.

PubMed

Pedowitz, Robert A; Nicandri, Gregg T; Angelo, Richard L; Ryu, Richard K N; Gallagher, Anthony G

2015-10-01

To assess a new method for biomechanical assessment of arthroscopic knots and to establish proficiency benchmarks using the Fundamentals of Arthroscopic Surgery Training (FAST) Program workstation and knot tester. The first study group included 20 faculty at an Arthroscopy Association of North America resident arthroscopy course (19.9 ± 8.25 years in practice). The second group comprised 30 experienced surgeons attending an Arthroscopy Association of North America fall course (17.1 ± 19.3 years in practice). The training group included 44 postgraduate year 4 or 5 orthopaedic residents in a randomized, prospective study of proficiency-based training, with 3 subgroups: group A, standard training (n = 14); group B, workstation practice (n = 14); and group C, proficiency-based progression using the knot tester (n = 16). Each subject tied 5 arthroscopic knots backed up by 3 reversed hitches on alternating posts. Knots were tied under video control around a metal mandrel through a cannula within an opaque dome (FAST workstation). Each suture loop was stressed statically at 15 lb for 15 seconds. A calibrated sizer measured loop expansion. Knot failure was defined as 3 mm of loop expansion or greater. In the faculty group, 24% of knots "failed" under load. Performance was inconsistent: 12 faculty had all knots pass, whereas 2 had all knots fail. In the second group of practicing surgeons, 21% of the knots failed under load. Overall, 56 of 250 knots (22%) tied by experienced surgeons failed. For the postgraduate year 4 or 5 residents, the aggregate knot failure rate was 26% for the 220 knots tied. Group C residents had an 11% knot failure rate (half the overall faculty rate, P = .013). The FAST workstation and knot tester offer a simple and reproducible educational approach for enhancement of arthroscopic knot-tying skills. Our data suggest that there is significant room for improvement in the quality and consistency of these important arthroscopic skills, even for experienced arthroscopic surgeons. Level II, prospective comparative study. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

[Survey of pain after ambulatory surgery: An internet-based instrument].

PubMed

Schwarze, C; Zenz, D; Orlowski, O; Wempe, C; Van Aken, H; Zahn, P; Maier, C; Pogatzki-Zahn, E M

2016-04-01

Pain after surgery continues to be undermanaged. Studies and initiatives aiming to improve the management of postoperative pain are growing; however, most studies focus on inpatients and pain on the first day after surgery. The management of postoperative pain after ambulatory surgery and for several days thereafter is not yet a major focus. One reason is the low return rate of the questionnaires in the ambulatory sector. This article reports the development and feasibility of a web-based electronic data collection system to examine pain and pain-related outcome on predefined postoperative days after ambulatory surgery. In this prospective pilot study 127 patients scheduled for ambulatory surgery were asked to participate in a survey to evaluate aspects related to pain after ambulatory surgery. The data survey was divided in (1) a preoperative, intraoperative and postoperative part and (2) a postoperative internet-based electronic questionnaire which was sent via e-mail link to the patient on days 1, 3 and 7 after surgery. A software was developed using a PHP-based platform to send e-mails and retrieve the data after web-based entries via a local browser. Feasibility, internet-based hitches and compliance were assessed by an additional telephone call after day 7. A total of 100 patients (50 female) between 18 and 71 years (mean 39.1 ± 12.7 years) were included in the pilot study. Return rates of the electronic questionnaires were 86% (days 3 and 7) and 91% (day 1 after surgery). All 3 electronic questionnaires were answered by 82% of patients. Aspects influencing the return rate of questionnaires were work status but not age, gender, education level and preoperative pain. Telephone interviews were performed with 81 patients and revealed high operability of the internet-based survey without any major problems. The user-friendly feasibility and operability of this internet-based electronic data survey system explain the high compliance and return rate of electronic questionnaires by patients at home after ambulatory surgery. This survey tool therefore provides unique opportunities to evaluate and improve postoperative pain management after ambulatory surgery.

Phonological working memory and FOXP2.

PubMed

Schulze, Katrin; Vargha-Khadem, Faraneh; Mishkin, Mortimer

2018-01-08

The discovery and description of the affected members of the KE family (aKE) initiated research on how genes enable the unique human trait of speech and language. Many aspects of this genetic influence on speech-related cognitive mechanisms are still elusive, e.g. if and how cognitive processes not directly involved in speech production are affected. In the current study we investigated the effect of the FOXP2 mutation on Working Memory (WM). Half the members of the multigenerational KE family have an inherited speech-language disorder, characterised as a verbal and orofacial dyspraxia caused by a mutation of the FOXP2 gene. The core phenotype of the affected KE members (aKE) is a deficiency in repeating words, especially complex non-words, and in coordinating oromotor sequences generally. Execution of oromotor sequences and repetition of phonological sequences both require WM, but to date the aKE's memory ability in this domain has not been examined in detail. To do so we used a test series based on the Baddeley and Hitch WM model, which posits that the central executive (CE), important for planning and manipulating information, works in conjunction with two modality-specific components: The phonological loop (PL), specialized for processing speech-based information; and the visuospatial sketchpad (VSSP), dedicated to processing visual and spatial information. We compared WM performance related to CE, PL, and VSSP function in five aKE and 15 healthy controls (including three unaffected members of the KE family who do not have the FOXP2 mutation). The aKE scored significantly below this control group on the PL component, but not on the VSSP or CE components. Further, the aKE were impaired relative to the controls not only in motor (i.e. articulatory) output but also on the recognition-based PL subtest (word-list matching), which does not require speech production. These results suggest that the aKE's impaired phonological WM may be due to a defect in subvocal rehearsal of speech-based material, and that this defect may be due in turn to compromised speech-based representations. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Working Memory From the Psychological and Neurosciences Perspectives: A Review.

PubMed

Chai, Wen Jia; Abd Hamid, Aini Ismafairus; Abdullah, Jafri Malin

2018-01-01

Since the concept of working memory was introduced over 50 years ago, different schools of thought have offered different definitions for working memory based on the various cognitive domains that it encompasses. The general consensus regarding working memory supports the idea that working memory is extensively involved in goal-directed behaviors in which information must be retained and manipulated to ensure successful task execution. Before the emergence of other competing models, the concept of working memory was described by the multicomponent working memory model proposed by Baddeley and Hitch. In the present article, the authors provide an overview of several working memory-relevant studies in order to harmonize the findings of working memory from the neurosciences and psychological standpoints, especially after citing evidence from past studies of healthy, aging, diseased, and/or lesioned brains. In particular, the theoretical framework behind working memory, in which the related domains that are considered to play a part in different frameworks (such as memory's capacity limit and temporary storage) are presented and discussed. From the neuroscience perspective, it has been established that working memory activates the fronto-parietal brain regions, including the prefrontal, cingulate, and parietal cortices. Recent studies have subsequently implicated the roles of subcortical regions (such as the midbrain and cerebellum) in working memory. Aging also appears to have modulatory effects on working memory; age interactions with emotion, caffeine and hormones appear to affect working memory performances at the neurobiological level. Moreover, working memory deficits are apparent in older individuals, who are susceptible to cognitive deterioration. Another younger population with working memory impairment consists of those with mental, developmental, and/or neurological disorders such as major depressive disorder and others. A less coherent and organized neural pattern has been consistently reported in these disadvantaged groups. Working memory of patients with traumatic brain injury was similarly affected and shown to have unusual neural activity (hyper- or hypoactivation) as a general observation. Decoding the underlying neural mechanisms of working memory helps support the current theoretical understandings concerning working memory, and at the same time provides insights into rehabilitation programs that target working memory impairments from neurophysiological or psychological aspects.

Human Temporal Cortical Single Neuron Activity During Working Memory Maintenance

PubMed Central

Zamora, Leona; Corina, David; Ojemann, George

2016-01-01

The Working Memory model of human memory, first introduced by Baddeley and Hitch (1974), has been one of the most influential psychological constructs in cognitive psychology and human neuroscience. However the neuronal correlates of core components of this model have yet to be fully elucidated. Here we present data from two studies where human temporal cortical single neuron activity was recorded during tasks differentially affecting the maintenance component of verbal working memory. In Study One we vary the presence or absence of distracting items for the entire period of memory storage. In Study Two we vary the duration of storage so that distractors filled all, or only one-third of the time the memory was stored. Extracellular single neuron recordings were obtained from 36 subjects undergoing awake temporal lobe resections for epilepsy, 25 in Study one, 11 in Study two. Recordings were obtained from a total of 166 lateral temporal cortex neurons during performance of one of these two tasks, 86 study one, 80 study two. Significant changes in activity with distractor manipulation were present in 74 of these neurons (45%), 38 Study one, 36 Study two. In 48 (65%) of those there was increased activity during the period when distracting items were absent, 26 Study One, 22 Study Two. The magnitude of this increase was greater for Study One, 47.6%, than Study Two, 8.1%, paralleling the reduction in memory errors in the absence of distracters, for Study One of 70.3%, Study Two 26.3% These findings establish that human lateral temporal cortex is part of the neural system for working memory, with activity during maintenance of that memory that parallels performance, suggesting it represents active rehearsal. In 31 of these neurons (65%) this activity was an extension of that during working memory encoding that differed significantly from the neural processes recorded during overt and silent language tasks without a recent memory component, 17 Study one, 14 Study two. Contrary to the Baddeley model, that activity during verbal working memory maintenance often represented activity specific to working memory rather than speech or language. PMID:27059210

The White Sea, Russia

NASA Technical Reports Server (NTRS)

2002-01-01

Editor's Note: The caption below, published on May 10, 2001, is incorrect. According to Masha Vorontsova, director of the International Fund for Animal Welfare in Moscow, the situation with the seal pups in the White Sea is normal. There is no disaster and there never was. For more details, refer to the article entitled 'No Danger' on the New Scientist home page. The Earth Observatory regrets the earlier errant report. Original Caption According to the Russian Polar Research Institute for Fisheries and Oceanography, between 250,000 and 300,000 Greenland seal pups face death by starvation over the next two months due to a cruel trick by mother nature. The seals, most of them less than two months old, are trapped on ice sheets that remain locked in the White Sea, located near Archangel in Northern Russia. Typically, during the spring thaw the ice sheets break up and flow with the currents northward into the Barents Sea, the seals' spring feeding grounds. The seal pups hitch a ride on the ice floes, living on their own individual stores of fat until they arrive in the Barents Sea. Their mothers departed for the Barents Sea weeks ago. In a normal year, the seal pups' trip from the White Sea out to the Barents takes about six weeks and the seals have adapted to rely upon this mechanism of mother nature. During their yearly migration, the mother seals usually stay with their pups and feed them until their pelts turn from white to grey--a sign that the pups are mature enough to swim and feed themselves. Unfortunately, this year unusually strong northerly winds created a bottleneck of ice near the mouth of the white sea, thus blocking the flow of ice and trapping the pups. These true-color images of the White Sea were acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. This image, taken May 2, 2000 that there is usually much less ice in the White Sea this time of year as most of it is typically en route to the Barents Sea.

Hitching a ride: Seed accrual rates on different types of vehicles.

PubMed

Rew, Lisa J; Brummer, Tyler J; Pollnac, Fredric W; Larson, Christian D; Taylor, Kimberley T; Taper, Mark L; Fleming, Joseph D; Balbach, Harold E

2018-01-15

Human activities, from resource extraction to recreation, are increasing global connectivity, especially to less-disturbed and previously inaccessible places. Such activities necessitate road networks and vehicles. Vehicles can transport reproductive plant propagules long distances, thereby increasing the risk of invasive plant species transport and dispersal. Subsequent invasions by less desirable species have significant implications for the future of threatened species and habitats. The goal of this study was to understand vehicle seed accrual by different vehicle types and under different driving conditions, and to evaluate different mitigation strategies. Using studies and experiments at four sites in the western USA we addressed three questions: How many seeds and species accumulate and are transported on vehicles? Does this differ with vehicle type, driving surface, surface conditions, and season? What is our ability to mitigate seed dispersal risk by cleaning vehicles? Our results demonstrated that vehicles accrue plant propagules, and driving surface, surface conditions, and season affect the rate of accrual: on- and off-trail summer seed accrual on all-terrain vehicles was 13 and 3508 seeds km -1 , respectively, and was higher in the fall than in the summer. Early season seed accrual on 4-wheel drive vehicles averaged 7 and 36 seeds km -1 on paved and unpaved roads respectively, under dry conditions. Furthermore, seed accrual on unpaved roads differed by vehicle type, with tracked vehicles accruing more than small and large 4-wheel drives; and small 4-wheel drives more than large. Rates were dramatically increased under wet surface conditions. Vehicles indiscriminately accrue a wide diversity of seeds (different life histories, forms and seed lengths); total richness, richness of annuals, biennials, forbs and shrubs, and seed length didn't differ among vehicle types, or additional seed bank samples. Our evaluation of portable vehicle wash units showed that approximately 80% of soil and seed was removed from dirty vehicles. This suggests that interception programs to reduce vehicular seed transportation risk are feasible and should be developed for areas of high conservation value, or where the spread of invasive species is of special concern. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Working Memory From the Psychological and Neurosciences Perspectives: A Review

PubMed Central

Chai, Wen Jia; Abd Hamid, Aini Ismafairus; Abdullah, Jafri Malin

2018-01-01

Since the concept of working memory was introduced over 50 years ago, different schools of thought have offered different definitions for working memory based on the various cognitive domains that it encompasses. The general consensus regarding working memory supports the idea that working memory is extensively involved in goal-directed behaviors in which information must be retained and manipulated to ensure successful task execution. Before the emergence of other competing models, the concept of working memory was described by the multicomponent working memory model proposed by Baddeley and Hitch. In the present article, the authors provide an overview of several working memory-relevant studies in order to harmonize the findings of working memory from the neurosciences and psychological standpoints, especially after citing evidence from past studies of healthy, aging, diseased, and/or lesioned brains. In particular, the theoretical framework behind working memory, in which the related domains that are considered to play a part in different frameworks (such as memory’s capacity limit and temporary storage) are presented and discussed. From the neuroscience perspective, it has been established that working memory activates the fronto-parietal brain regions, including the prefrontal, cingulate, and parietal cortices. Recent studies have subsequently implicated the roles of subcortical regions (such as the midbrain and cerebellum) in working memory. Aging also appears to have modulatory effects on working memory; age interactions with emotion, caffeine and hormones appear to affect working memory performances at the neurobiological level. Moreover, working memory deficits are apparent in older individuals, who are susceptible to cognitive deterioration. Another younger population with working memory impairment consists of those with mental, developmental, and/or neurological disorders such as major depressive disorder and others. A less coherent and organized neural pattern has been consistently reported in these disadvantaged groups. Working memory of patients with traumatic brain injury was similarly affected and shown to have unusual neural activity (hyper- or hypoactivation) as a general observation. Decoding the underlying neural mechanisms of working memory helps support the current theoretical understandings concerning working memory, and at the same time provides insights into rehabilitation programs that target working memory impairments from neurophysiological or psychological aspects. PMID:29636715

EcAMSat and BioSentinel: Autonomous Bio Nanosatellites Addressing Strategic Knowledge Gaps for Manned Spaceflight Beyond LEO

NASA Technical Reports Server (NTRS)

Padgen, Michael R.

2017-01-01

Manned missions beyond low Earth orbit (LEO) require that several strategic knowledge gaps about the effects of space travel on the human body be addressed. NASA Ames Research Center has been the leader in developing autonomous bio nanosatellites, including past successful missions for GeneSat, PharmaSat, and O/OREOS, that tackled some of these issues. These nanosatellites provide in situ measurements, which deliver insight into the dynamic changes in cell behavior in microgravity. In this talk, two upcoming bio nanosatellites developed at Ames, the E. coli Antimicrobial Satellite (EcAMSat) and BioSentinel, will be discussed. Both satellites contain microfluidic systems that precisely deliver nutrients to the microorganisms stored within wells of fluidic cards. Each well, in turn, has its own 3-color LED and detector system which is used to monitor changes in metabolic activity with alamarBlue, a redox indicator, and the optical density of the cells. EcAMSat investigates the effects of microgravity on bacterial resistance to antimicrobial drugs, vital knowledge for understanding how to maintain the health of astronauts in long-term and beyond LEO spaceflight. The behavior of wild type and mutant uropathic E. coli will be compared in microgravity and with ground data to help understand the molecular mechanisms behind antibiotic resistance and how these phenotypes might change in space. BioSentinel seeks to directly measure the effects of space radiation on budding yeast S. cerevisiae, particularly double strand breaks (DSB). While hitching a ride on the SLS EM-1 mission (Orion's first unmanned mission to the moon) in 2018, BioSentinel will be kicked off and enter into a heliocentric orbit, becoming the first study of the effects of radiation on living organisms outside LEO since the Apollo program. The yeast are stored in eighteen independent 16-well microfluidic cards, which will be individually activated over the 12 month mission duration. In addition to the wild type and radiation-sensitive mutant strains, a BioSentinel strain of yeast has been developed, which requires a DSB to reactivate growth, thereby allowing for a direct measurement of DSBs caused by radiation. These two missions demonstrate the utility of using autonomous nanosatellites to address strategic knowledge gaps in the push to once again extend manned spaceflight beyond LEO.

EcAMSat and BioSentinel: Autonomous Bio Nanosatellites Addressing Strategic Knowledge Gaps for Manned Spaceflight Beyond LEO

NASA Technical Reports Server (NTRS)

Padgen, Mike

2017-01-01

Manned missions beyond low Earth orbit (LEO) require that several strategic knowledge gaps about the effects of space travel on the human body be addressed. NASA Ames Research Center has been the leader in developing autonomous bio nanosatellites, including past successful missions for GeneSat, PharmaSat, and OOREOS, that tackled some of these issues. These nanosatellites provide in situ measurements, which deliver insight into the dynamic changes in cell behavior in microgravity. In this talk, two upcoming bio nanosatellites developed at Ames, the E. coli Antimicrobial Satellite (EcAMSat) and BioSentinel, will be discussed. Both satellites contain microfluidic systems that precisely deliver nutrients to the microorganisms stored within wells of fluidic cards. Each well, in turn, has its own 3-color LED and detector system which is used to monitor changes in metabolic activity with alamarBlue, a redox indicator, and the optical density of the cells. EcAMSat investigates the effects of microgravity on bacterial resistance to antimicrobial drugs, vital knowledge for understanding how to maintain the health of astronauts in long-term and beyond LEO spaceflight. The behavior of wild type and mutant uropathic E. coli will be compared in microgravity and with ground data to help understand the molecular mechanisms behind antibiotic resistance and how these phenotypes might change in space. BioSentinel seeks to directly measure the effects of space radiation on budding yeast S. cerevisiae, particularly double strand breaks (DSB). While hitching a ride on the SLS EM-1 mission (Orions first unmanned mission to the moon) in 2018, BioSentinel will be kicked off and enter into a heliocentric orbit, becoming the first study of the effects of radiation on living organisms outside LEO since the Apollo program. The yeast are stored in eighteen independent 16-well microfluidic cards, which will be individually activated over the 12 month mission duration. In addition to the wild type and radiation-sensitive mutant strains, a BioSentinel strain of yeast has been developed, which requires a DSB to reactivate growth, thereby allowing for a direct measurement of DSBs caused by radiation. These two missions demonstrate the utility of using autonomous nanosatellites to address strategic knowledge gaps in the push to once again extend manned spaceflight beyond LEO.

Conservation and protection

USGS Publications Warehouse

Leopold, Luna Bergere

1960-01-01

When I was a child we had a burro I called Gacho. He was a typical burro, omnivorous in his eating habits and prone to streaks of extreme recalcitrance.Our yard wasn't very large, but it did produce enough grass and weeds to keep old Gacho in good fettle. His first preference was for the native grasses, and he chose to graze the lush patches rather than the shriveled plants on the areas of thin soil. Nevertheless, he was not particular and seemed to graze to some extent all over the yard. He often nibbled in the flower beds and I sometimes wondered whether he did this just for spite.After a time I arranged some crude fences and a tethering rope to keep him out of the most important flower beds.The yard was so small that we had a waste problem. To ignore the problem would hardly have been civilized, but, on the other hand, one couldn't follow him around all day with a shovel. So a workable compromise was adopted by keeping him penned up at night in a small enclosure, which, of course, could not be kept immaculate but was at least reasonably clean.We had the burro and we weren't getting rid of him. He was useful; we enjoyed riding him and hitching him up to our wagons. But he was a bother sometimes.Here was a simple case of resource use and resource development. The case is incomplete, but it demonstrates a principle.The resource, represented by the vegetation, was being utilized, or developed if you will, by a small juggernaut which was only partly controllable by my youthful skills. There was no need to urge utilization. That followed as a matter of course. The problem was that the one who utilized the resource, in this case the burro, was not very discerning of relative values. To Gacho the choice of which plant to eat and where to get rid of the waste was governed only by his own interests and convenience.Now, when a planning body convenes, one may bet that either the burro has Jain down in a flower bed or he has messed up the yard. By this time everybody is already in a lather.An appreciation of the existence of problems usually leads to a period of organizing the facts, assessing the current situation, and surveying the future possibilities. In the New England area such an assessment has recently been completed. Since that stage has been reached, it is logical to discuss the function of a planning unit as a prelude to the next phase. I should like to outline my own thoughts on this matter, but I do so without expecting to convince all others.

Hydrocarbon Development from Shale: A Set of Important, Unsolved Problems

NASA Astrophysics Data System (ADS)

Ingraffea, A. R.; Burchell, A.; Howarth, R.; Wilson, A.; Doe, P.; Colborn, T.; Wood, M. C.

2013-12-01

Hydraulic fracturing has become synonymous with the new technologies and processes used to develop oil and methane from shale formations. We will address the following important set of problems associated with such development and the role scientists are playing in communicating these to the public. Human Health Consequences: The health consequences of the wide-range of fugitive hydrocarbon emissions associated with methane and oil are not adequately addressed. New evidence about exposure to, and the known and possible health effects of, these toxic hitch hikers will be presented. Methane Emissions: Methane is a more powerful greenhouse gas than carbon dioxide, though atmospheric residence is shorter. Methane is emitted through-out the development life-cycle, albeit there is uncertainty over the rate, and short-term effect on global warming. Leakage from Faulty Wells: Multiple industry studies show that about 5 percent of oil and gas wells immediately leak methane and other fluids into the atmosphere and water wells due to integrity issues and increasing rates of leakage over time. With millions of wells drilled worldwide, and millions more expected, this problem is neither negligible nor preventable with current technology. Federal Exemptions and Home Rule: 'Fracking' currently slips through federal environmental statutory law because of an industry-friendly exemption. However, trusts are established in US law and the Public Trust Doctrine provides a basis for courts to enjoin 'fracking' due to the potential impact on beneficiaries of the trust --present and future generations. The public trust designates government as a trustee of crucial resources and imposes a fiduciary obligation on agencies to prevent "substantial impairment" of- and protect access to- clean air, clean water and other natural resources vital for public welfare and survival. Already applied to the realm of ecology, the doctrine is reviewed as a legal and policy toot to protect communities threatened by 'fracking.' Additionally, 'oil and gas - rights' Legislation and State Supreme Court decisions in communities underlain by shale deposits has been to silence 'Home-Rule' rights. The post-extraction impact of such rulings on public health and property values is dramatic. Soil Quality: Fracking poses a serious threat to soil quality and underlines the crucial role that soils can play in mitigating climate change. In addition to critical ecosystem and agricultural benefits, healthy soils represent a significant natural carbon reservoir. Enhancing the Natural Terrestrial Sequestration (NTS) potential of soils is an important carbon management strategy. Our studies reveal undisturbed soils underlain by intermediate to mafic volcanic rocks and shale formations sampled can have 2 to 6 times greater total organic soil carbon (TOSC) than global averages. However, anthropogenic disturbed-lands now represent the 7th largest- land class (ISRIC, US-DOI) and may account for a significant reduction in NTS potential. EPA studies indicate 20 to 85% of frack-fluids are not recovered. This could continue to be a long-term source of soil and groundwater contamination - risking further decreased NTS potential.

Efficient mapping of agricultural soils using a novel electromagnetic measurement system

NASA Astrophysics Data System (ADS)

Trinks, Immo; Pregesbauer, Michael

2016-04-01

"Despite all our accomplishments, we owe our existence to a six-inch layer of topsoil and the fact that it rains." - Paul Harvey. Despite the fact, that a farmers most precious good is the soil that he or she cultivates, in most cases actually very little is known about the soils that are being farmed. Agricultural soils are under constant threat through erosion, depletion, pollution and other degrading processes, in particular when considering intensive industrial scale farming. The capability of soils to retain water and soil moisture is of vital importance for their agricultural potential. Detailed knowledge of the physical properties of soils, their types and texture, water content and the depth of the agricultural layer would be of great importance for resource-efficient tillage with sub-area dependent variable depth, and the targeted intelligent application of fertilizers or irrigation. Precision farming, which has seen increasing popularity in the USA as well as Australia, is still in its infancy in Europe. Traditional near-surface geophysical prospection systems for agricultural soil mapping have either been based on earth resistance measurements using electrode-disks that require soil contact, with inherent issues, or electromagnetic induction (EMI) measurements conducted with EMI devices mounted in non-metallic sledges towed several metres behind survey vehicles across the fields. Every farmer passes over the fields several times during each growing season, working the soil and treating the crops. Therefore a novel user-friendly measurement system, the "Topsoil Mapper" (TSM) has been developed, which enables the farmer to simultaneously acquire soil conductivity information and derived soil parameters while anyway passing over the fields using different agricultural implements. The measurement principle of the TSM is electromagnetic induction using a multi-coil array to acquire conductivity information along a vertical profile down to approximately 1.1 m depth. Instead of being towed several metres behind the tractor, as common with traditional EMI systems used in precision farming, the novel device is conveniently mounted on the front hitch of a tractor and operated from a terminal in the driver's cabin. A major improvement compared with existing EMI systems is the system's capability to cope with the induced noise from the tractor, through integration of a mechanical shielding mechanism into the sensor housing. Any remaining vehicle induced high-frequency electromagnetic noise is filtered out on-the-fly by the data acquisition software, logging the data and positioning information on a ruggedized small computer. The main purpose of this system is to permit the land owner or farmer the efficient mapping of the electrical soil conductivity across agricultural fields on the scale of the entire acreage. The main objective of the measurements is to obtain detailed information on the long wavelength variability of soil structure, while eliminating short wavelength variations. The calculation of the depth of the agricultural layer, or topsoil thickness, has been implemented by inverting the cumulative response function for all coil configurations. The resulting inverted models of the soil conductivity display the vertical distribution of agriculturally relevant soil parameters and improve the chances to identify different subsoil features. By providing this information on the shallow subsurface in real-time, while passing across the field, permits the agriculturist to variably adjust for instance tillage depth or to control other agricultural implements and machines based to the derived information, rendering the soil cultivation both ecologically as well as economically more efficient. We present the TSM system as well as derived data examples.

Designing a Gamma-Ray Telescope on a Budget

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-05-01

Major space-based observatories are imperative in astronomy, but they take a long time to plan, build, and launch and they arent cheap. A new study examines an interesting compromise: a low-cost, space-based gamma-ray detector that we could use while we wait for the next big observatory to launch.Coverage and sensitivity of past and future missions for the X-ray to gamma-ray energy range (click for a better look!). The only past mission to explore the 1 MeV region was COMPTEL, on board CGRO. e-ASTROGAM is a proposed future space mission that would explore this range. [Lucchetta et al. 2017]A Gap in CoverageIn the last few decades, weve significantly expanded our X-ray and gamma-ray viewof the sky. One part of the electromagnetic spectrum remains poorly explored, however: the approximate transition point between X-rays and gamma rays near 1 MeV.Space-based gamma-ray telescopes have been proposed for the future to better explore this energy range. But these major observatories have costs of around half a billion Euros and will take roughly a decade to build and launch. Is there a way to get eyes on this energy range sooner?Scaling Down with CubeSatA team of scientists led by Giulio Lucchetta (University of Padova and INFN Padova, Italy) has proposed an intriguing solution for the more immediate future: a nano-satellite telescope based on the CubeSat standard.Structure of the proposed gamma-ray detector, in a 2U CubeSat design. [Lucchetta et al. 2017]A CubeSat is a miniaturized satellite design that can be easily deployed in space, either from the International Space Station or by hitching a ride as a secondary payload on a large rocket. The size of a CubeSat is a standardized unit of measurement: a single CubeSat unit, or 1U, is a mere 10x10x10 cm and a maximum of 1.33 kg in weight.The gamma-ray telescope proposed by Lucchetta and collaborators would use a 2U standard for the instrument, so the instrument would be only 10x10x20 cm in size! The design for the telescope as a whole including the on-board electronics and flight system would likely require a 4U model.The teams proposed nanoscale observatory would be capable of detecting gamma rays from 100 keV up to a few MeV. In comparison to the major space-based observatories, this project would be very low-cost, at only half a million Euros and such a telescope could go from build to launch in about a year.Evaluating PerformanceEstimated sensitivity of the proposed nanoscale satellite telescope (for tracked, untracked, and pair production events) compared to that of COMPTEL. [Lucchetta et al. 2017]Cheaper and faster is great, but how would this project do in terms of quality? The authors performed simulations to examine the scientific performance of the proposed detector, evaluating its effective area, energy resolution, and angular resolution. Luchetta and collaborators show that while the scientific performance would be well below that expected for large future missions, it would likely be on par with the last detector to observe this region COMPTEL, on board the Compton Gamma Ray Observatory.It seems that a nanoscale satellite like this one would helpfully cover the gap around 1 MeV and allow us to learn more about low-energy gamma rays while we wait for large future missions to launch. As an additional benefit, such a project could serve as a pathfinder mission to test technologies and algorithms to be used in larger missions in the future.CitationGiulio Lucchetta et al 2017 AJ 153 237. doi:10.3847/1538-3881/aa6a1b

Astronomers Gain Important Insight on How Massive Stars Form

NASA Astrophysics Data System (ADS)

2006-09-01

Astronomers using the National Science Foundation's Very Large Array (VLA) radio telescope have discovered key evidence that may help them figure out how very massive stars can form. Young Star Graphic Artist's Conception of Young Star Showing Motions Detected in G24 A1: (1) Infall toward torus, (2) Rotation and (3) outflow. CREDIT: Bill Saxton, NRAO/AUI/NSF Click on image for larger graphic file (JPEG, 129K) "We think we know how stars like the Sun are formed, but there are major problems in determining how a star 10 times more massive than the Sun can accumulate that much mass. The new observations with the VLA have provided important clues to resolving that mystery," said Maria Teresa Beltran, of the University of Barcelona in Spain. Beltran and other astronomers from Italy and Hawaii studied a young, massive star called G24 A1 about 25,000 light-years from Earth. This object is about 20 times more massive than the Sun. The scientists reported their findings in the September 28 issue of the journal Nature. Stars form when giant interstellar clouds of gas and dust collapse gravitationally, compacting the material into what becomes the star. While astronomers believe they understand this process reasonably well for smaller stars, the theoretical framework ran into a hitch with larger stars. "When a star gets up to about eight times the mass of the Sun, it pours out enough light and other radiation to stop the further infall of material," Beltran explained. "We know there are many stars bigger than that, so the question is, how do they get that much mass?" One idea is that infalling matter forms a disk whirling around the star. With most of the radiation escaping without hitting the disk, material can continue to fall into the star from the disk. According to this model, some material will be flung outward along the rotation axis of the disk into powerful outflows. "If this model is correct, there should be material falling inward, rushing outward and rotating around the star all at the same time," Beltran said. "In fact, that's exactly what we saw in G24 A1. It's the first time all three types of motion have been seen in a single young massive star," she added. The scientists traced motions in gas around the young star by studying radio waves emitted by ammonia molecules at a frequency near 23 GHz. The Doppler shift in the frequency of the radio waves gave them the information on the motions of the gas. This technique allowed them to detect gas falling inward toward a large "doughnut," or torus, surrounding the disk presumed to be orbiting the young star. "Our detection of gas falling inward toward the star is an important milestone," Beltran said. The infall of the gas is consistent with the idea of material accreting onto the star in a non-spherical manner, such as in a disk. This supports that idea, which is one of several proposed ways for massive stars to accumulate their great bulk. Others include collisions of smaller stars. "Our findings suggest that the disk model is a plausible way to make stars up to 20 times the mass of the Sun. We'll continue to study G24 A1 and other objects to improve our understanding," Beltran said. Beltran worked with Riccardo Cesaroni and Leonardo Testi of the Astrophysical Observatory of Arcetri of INAF in Firenze, Italy, Claudio Codella and Luca Olmi of the Institute of Radioastronomy of INAF in Firenze, Italy, and Ray Furuya of the Japanese Subaru Telescope in Hawaii. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

Jets from Merging Neutron Stars

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2016-06-01

With the recent discovery of gravitational waves from the merger of two black holes, its especially important to understand the electromagnetic signals resulting from mergers of compact objects. New simulations successfully follow a merger of two neutron stars that produces a short burst of energy via a jet consistent with short gamma-ray burst (sGRB) detections.Still from the authors simulation showing the two neutron stars, and their magnetic fields, before merger. [Adapted from Ruiz et al. 2016]Challenging SystemWe have long suspected that sGRBs are produced by the mergers of compact objects, but this model has been difficult to prove. One major hitch is that modeling the process of merger and sGRB launch is very difficult, due to the fact that these extreme systems involve magnetic fields, fluids and full general relativity.Traditionally, simulations are only able to track such mergers over short periods of time. But in a recent study, Milton Ruiz (University of Illinois at Urbana-Champaign and Industrial University of Santander, Colombia) and coauthors Ryan Lang, Vasileios Paschalidis and Stuart Shapiro have modeled a binary neutron star system all the way through the process of inspiral, merger, and the launch of a jet.A Merger TimelineHow does this happen? Lets walk through one of the teams simulations, in which dipole magnetic field lines thread through the interior of each neutron star and extend beyond its surface(like magnetic fields found in pulsars). In this example, the two neutron stars each have a mass of 1.625 solar masses.Simulation start (0 ms)Loss of energy via gravitational waves cause the neutron stars to inspiral.Merger (3.5 ms)The neutron stars are stretched by tidal effects and make contact. Their merger produces a hypermassive neutron star that is supported against collapse by its differential (nonuniform) rotation.Delayed collapse into a black hole (21.5 ms)Once the differential rotation is redistributed by magnetic fields and partially radiated away in gravitational waves, the hypermassive neutron star loses its support and collapses to a black hole.Plasma velocities turn around (51.5 ms)Initially the plasma was falling inward, but as the disk of neutron-star debris is accreted onto the black hole, energy is released. This turns the plasma near the black hole poles around and flings it outward.Magnetic field forms a helical funnel (62.5 ms)The fields near the poles of the black hole amplify as they are wound around, creating a funnel that provides the wall of the jet.Jet outflow extends to heights greater than 445 km (64.5 ms)The disk is all accreted and, since the fuel is exhausted, the outflow shuts off (within 100ms)Neutron-Star SuccessPlot showing the gravitational wave signature for one of the authors simulations. The moments of merger of the neutron stars and collapse to a black hole are marked. [Adapted from Ruiz et al. 2016]These simulations show that no initial black hole is needed to launch outflows; a merger of two neutron stars can result in an sGRB-like jet. Another interesting result is that the magnetic field configuration doesnt affect the formation of a jet: neutron stars with magnetic fields confined to their interiors launch jets as effectively as those with pulsar-like magnetic fields. The accretion timescale for both cases is consistent with the duration of an sGRB.While this simulation models milliseconds of real time, its enormously computationally challenging and takes months to simulate. The successes of this simulation represent exciting advances in numerical relativity, as well as in our understanding of the electromagnetic counterparts that may accompany gravitational waves.BonusCheck out this awesome video of the authors simulations. The colors differentiate the plasma density and the white lines depict the pulsar-like magnetic field that initially threads the two merging neutron stars. Watch as the neutron stars evolve through the different stages outlined above, eventually forming a black hole and launching a powerful jet.[Simulations and visualization by M. Ruiz, R. Lang, V. Paschalidis, S. Shapiro and the Illinois Relativity Group REU team: S. Connelly, C. Fan, A. Khan, and P. Wongsutthikoson]CitationMilton Ruiz et al 2016 ApJ 824 L6. doi:10.3847/2041-8205/824/1/L6

Houston, We Have a Podcast. Episode 50: DNA Sequencing

NASA Image and Video Library

2018-06-22

Gary Jordan (Host): Houston, We Have a Podcast. Welcome to the official podcast of the NASA Johnson Space Center, episode 50, DNA sequencing. I'm Gary Jordan, and I'll be your host today. On this podcast we bring in the experts, NASA scientists, engineers and astronauts, all to let you know the coolest information about what's going on right here at NASA. So today we're talking about DNA sequencing on board the International Space Station with Dr. Sarah Wallace. First a little background, DNA stands for deoxyribonucleic acid. This basically serves as a blueprint for any organism. DNA provides detailed instructions on how to make a living thing what it is, whether it's a banana tree, bunny rabbit or human being. DNA sequencing is when you take a small sample of a living thing, such as a mold from the kitchen sink or cheek cells from your mouth and extract the DNA from the cells. Then you determine the order of the nucleotide basis. This is the order then that's matched with the patterns of known organisms. Thirty years ago, first-generation DNA sequencing machines could easily take up an entire laboratory's worth of space. Now we're using a sequencer on the International Space Station that could literally fit inside of a pocket. So today, we're talking with Dr. Sarah Wallace who was instrumental in developing this sequencer as part of a multicenter effort led right here at the Johnson Space Center. I'm particularly excited about this interview because DNA sequencing can be used for all sorts of beneficial things in space from monitoring the crew members' health to identifying microbes, and even potentially detecting life in the solar system. So with no further delay, let's go light speed and jump right ahead to our talk with Dr. Sarah Wallace. Enjoy. ~- [ Music ] Host: Sarah, thank you so much for coming on the podcast today. Very excited for this topic because DNA sequencing, this is relatively new for spaceflight in particular, but it sounds super cool, but if you kind of know what it is. And that's the thing is whenever I was like cool, yeah, DNA sequencing in space. What is that? So, if we can just start there. What's DNA sequencing? Sarah Wallace: Sure, so DNA sequencing, like you mentioned, not new to labs here on Earth. Host: Yeah. Sarah Wallace: Definitely brand new to space. Traditionally, you know, we've been doing DNA sequencing on the ground for a couple decades now through different methods of doing it. But it's definitely evolved to the point where the instrumentation could be small and portable enough that we could do it in space. The old, most of the sequencers, the other two that I have in my lab, they're very large. They're sensitive to vibrations. They require a large power draw. As you know, those are not things that are awesome for spaceflight. Makes things a little difficult. So when this new technology came out that would really let us achieve the same thing, which is obtaining the sequence of DNA in a smaller platform, that's what's really allowed us to do it in space. So really, DNA sequencing is just that, just determining that order of those four bases, the A, the G, the T and the C, that if you sometimes see all those kind of, just looks like a bunch of letters and looks like it doesn't mean anything. But that's that sequence that makes up every living thing. And so this instrument is letting us determine that sequence. Host: So I hate to back up even further than that, but you're talking to a marketing major here. So if we're to backup to DNA and these four letters, what is that? Sarah Wallace: So they're made of, these are the nucleotide bases, so that's really a sugar phosphate backbone that you have these, the bases on. So, do you just want me to say deoxyribonucleic acid? Host: Yeah. Sarah Wallace: Okay, like I didn't know, like am I going too simple? Okay. So deoxyribonucleic acid, and so this is really, again, like it makes up every living thing. And so it's, you know, one of the basic building blocks, or the basic thing that makes up these blueprints that we know all lifeforms on Earth have this very similar, incredibly similar structure that if we can determine the sequence, that can tell us, either tell us all about that living thing, even if it's something small like a microorganism. Even tells who that living thing is. So it's really just an abundance of information that we can get on something. Host: So, basically, the order of these four things spread out over how many characters? Millions? Or is it millions? Sarah Wallace: Yeah. Yep, depending on if we're talking about for a human or for a plant or for bacteria. You're going to have different size genomes. So this makes up your genome. And so what those four letters do is that they code for genes. So a sequence of these four letters make up a gene. And it's those genes and the way that they get turned on and off that tells our bodies how to respond to certain environments, and they're telling our cells when to grow and when to, you know, all these different things. So by looking at the DNA, we have the genes. And then we need to take it a step further to look at the RNA which is, DNA is transcribed into RNA. And so by looking at the RNA, which is what our next experiment is going to do, that gets back to the telling us which genes are on and off. So the DNA in theory should always be the same, unless it's changed by something like a mutation. Now your gene expression, that's something that's changing all the time. And we do that by measuring the RNA. Host: Interesting. This is a complicated world. Sarah Wallace: It is. I'm sorry. I'm not doing a good job. Host: No, you're doing great. It's me who didn't study enough in school. Sarah Wallace: Well, and I'm jumping ahead and all over the place. Host: But if I were to sort of take it down to my brain capacity, this, a gene, for example, is, and correct me if I'm wrong, the color of your hair. So a gene is going to say, you have brown hair. Sarah Wallace: Yep. Host: And then this sequence is going to say, this person is going to have brown hair based on this gene. Sarah Wallace: Right. Host: Okay. Sarah Wallace: Yeah. Host: But it doesn't, it's not like it's going to identify this long string of letters and just like this is Dr. Sarah Wallace. Sarah Wallace: We're getting there. Host: Really? Sarah Wallace: Yeah, we're getting there. So with a microorganism, that's exactly what it's going to do. It's going to tell me who that microorganism is. And for me as a microbiologist, that's what I want to know. Host: That's awesome. Sarah Wallace: I want to know, yep, I want to know who that is that could potentially make the crew sick or be a problem to the ISS environment. A lot, there's a lot of companies, I'm sure you've seen the commercials on TV for send us your DNA sample, and we'll tell you all about you. Host: Yeah. Sarah Wallace: They're getting into the, it's getting pretty specific to where if you, you know, you can find out a lot about somebody's background, their heritage, maybe what certain, you know, diseases they might be more likely to have. So it's, we're kind of right at that point I think. And again, I'm a microbiologist, not human. But a dose of the human genomes. But we're kind of right at the cusp of where that's really starting to take off to where you could start looking at things like personalized medicine based on your genome. And that's really where a lot of research is headed. Host: Is it fair to say that that's huge. Sarah Wallace: Uh-huh. Host: Yeah. Sarah Wallace: Yeah. Host: That's a big one, right? Sarah Wallace: Yeah. And, you know, especially for NASA. These are, you know, we have a, you know our crew is, you know, they're a healthy population. So, you know, we're not looking necessarily if they have these diseases, but if there were a way where we could understand if a crew was more, would metabolize a certain nutrient better, or there was a way we could alter it based on their genome, that may be a countermeasure for being able to, you know, if certain nutrients are limited or, you know, the body isn't absorbing them, that you could really handle that at the level of the genome. Host: So you can basically identify where the gaps are, and you say you need this extra nutrient. Okay, add this to the diet. Or, yeah basically -- Sarah Wallace: Or if they're taking it in, but they're just not metabolizing it. And so they're getting plenty of it, but it's being excreted in their urine because their body isn't metabolizing it as well as somebody else's. So maybe there's other things that you can do to help them increase their metabolism of that nutrient. Host: Yeah. Sarah Wallace: But the research is already kind of headed in that direction. Host: Like maybe some sort of pharmaceutical that can help them to digest or something like that. Sarah Wallace: Same thing. Same thing, yep. Yep. Host: Okay. Sarah Wallace: And maybe someone is more prone to be susceptible to a certain type of pharmaceutical or somebody else wouldn't be. And those are things that we're starting to really look at the level of the genome to provide insight towards. Host: Wow, okay, so I guess, there's a lot of things to look forward to in the future, but in terms of DNA sequencing, I guess right now on the Station, we'll start with what are we doing now? What are we learning now on the Station with sequencing? Sarah Wallace: So our very first experiment on the biomolecule sequencer -- Host: Yeah. Sarah Wallace: Dr. Aaron Burton was the principal investigator of that experiment. That was really to take this new piece of technology, this very small sequencer that, again, the output of what it gives you is the same as these big ones. It just does it in a very different way. But does this even work in microgravity? Before we start developing a lot of ways to prepare the sample, does this thing even work? So that was the first experiment. And that's the one that, you know, Kate Rubins, I think that picture's been seen a lot, her holding it with her success, the first DNA sequencing. And that's really what it was. We prepared the DNA on the ground here on Earth. And then we launched the DNA. We launched the sequencer. And everything worked beautifully. Much better than we could have expected. And so then the follow one that we were already working on at the same time, we had gotten funding to develop, was that sample prep process. Because the sequencer is no good if you don't have a way to prep your sample. And every sequencer, this very tiny one to the larger ones, you have to put the DNA in a state that the sequencer can recognize it or read it. So that sample preparation part is key no matter what DNA sequencer you're using. So that was really where the, where some of the got yous would be is how do I basically put my entire molecular biology lab on ISS? And so what we were really doing was finding ways, you know, using what was already out there and technology that was already up there, and just how can we tweak procedures to make this as easy for the crew to do as possible but get us meaningful science. Host: Did size have a lot to do with it? You were constrained on how much you can bring up and how much you can have, you know. Sarah Wallace: Exactly. Host: Yeah, yeah, yeah. Sarah Wallace: Size and power and, you know, something that we use a lot of on the ground is a centrifuge. And while there are centrifuges up there, they're not, they're not exactly the same ones we would use for this type of, you know, to do the molecular biology where you just quickly pop in a little tube in and out. They're very specialized. So they weren't available to us. So it was actually a piece of equipment that was already up there that was called mini PCR. And that PCR stands for the polymerase chain reaction. And that process is just amplifying DNA. So you can think of it kind of like a photocopier for DNA. So if you have a very little amount, you can turn it into a lot. And that's a common first step in any molecular biology process but especially DNA sequencing. That's usually a first step thing you're going to do. So that was already on board. It was actually, the Genes in Space program, which is a high school student, high school students get involved, and they can propose an experiment. So the first molecular biology experiment ever done in space as a high school student, which I think is just cool. I just think, you know, way to go. Host: Yeah. Sarah Wallace: And so we were able to partner with them, our biomolecule sequencer and mini PCR, and we became Genes in Space-3. And so what that was, Genes in Space-3 was really to show that we could go all the way from a sample to an answer. And what we chose as our sample for that was actually microorganisms that have been collected from and cultured on ISS as part of my lab's normal job is to monitor the ISS air, water and surface for what's growing up there. So we already have this stuff growing up there, but it wasn't a part of our process. So we were able to pull in some of those bacteria and actually have the astronaut sequence them on board, which is the first time we've ever identified anything off planet Earth. So super exciting. Host: So the sample was the stuff that's growing. What's growing? What's growing up there? Sarah Wallace: Well, it's not all necessarily growing, but some of it is. There's everything. So ISS has a microbiome just like we do. So, every, you know, we don't send up a sterile vehicle. We don't send up sterile crew. We don't send up sterile anything. You know, cargo, hardware, food, everything has microorganisms that it's taking up there. Host: It's as sterile as we can make it, but -- Sarah Wallace: Well, and we do our best to reduce potential pathogens from getting up there. But as I think we're starting to learn, there's a healthy balance. There's very beneficial microbes. And we're still working on understanding how those in the environment interplay with us as humans in our daily life. That research is just starting to get underway. Host: Yeah. Sarah Wallace: But, what we want to do is make sure that some of those potential pathogens that we carry with us aren't there in high abundance to where a crew could come in contact with them, or they would get into the water system and something could foul up the water system and cause problems for the vehicle that would be a problem for everybody. Host: Yeah. Sarah Wallace: So that's part of our normal. We've been doing that since the beginning of Station. Host: Right. Sarah Wallace: And the astronauts actually are physically culturing the bacteria and the fungi that are up there. Host: Is this a normal part of living in a contained environment, I guess? No matter what kind of contained environment, there's going to be this microbiome -- Sarah Wallace: Absolutely. Host: these fungi bacterial that are just going to. But you have to learn to coexist with them in this type space. Sarah Wallace: Absolutely. Right. Host: And that's really what it is. Sarah Wallace: Yeah, and really just reducing the risk. If we find something that, there are definitely things we carry as people, but you know, they're fine when they're on us. But we don't want them out in the environment in high numbers where the crew has a scrape or something. They accidently bump up against it. They get it in there. You know, there's, we just want to have the environment be as free of those types of things as possible. Host: Sure. Sarah Wallace: And also the things, like I said, that could foul up one of the environmental life support systems because something's growing in them. Which is something we have to keep a close eye on. So, that's really the why we do this monitoring in the first place is just to see, making sure the environment is leading to the least amount of risk possible. Host: So what's the normal monitoring that you do? And then what was this, you said there was a sample and then answer section of the DNA. Sarah Wallace: Yes. Yep. Host: So what are those two components? Sarah Wallace: So the normal monitoring is this basic have the astronaut collect from the air, the water, the surface, a sample, and actually grow the bacteria and the fungi. That's what we do all the time. Host: Cool. Sarah Wallace: Then we get about an idea of about how many is there, but we have no idea what it is. And as a microbiologist, I would argue that oftentimes, with some of these environmental bugs, sometimes what it is can be more important than how many there are. When you drink water, you're drinking bacteria, and it could be in relatively high number. They don't hurt you, but if just a few of the wrong type are in there, you're in for a rough night. And anybody that's ever had food poisoning or anything kind of knows, yeah. You don't want the crew to experience that. So, it's really important to know what it is, not just how many there are. So we, up until very recently, we have never been able to have that answer in space. We have to wait until those samples come back to the lab on the ground here and for our microbiologists to be able to process them and provide an answer. And we do that through DNA sequencing. So now, with Genes in Space-3, we were able to take one of those samples that we would normally return, and we were able to actually have the astronaut take some of the cells that had been grown and put them through our mini PCR process into the MinION, which is the DNA sequencer, and actually, we were able to get the data down of what was growing on those petri dishes before we even got the petri dish back. So that was, again, that's really something we need to be able to enable, you know, human exploration beyond ISS. So it was, for me, that was one of the most exciting moments I've ever had in my career was seeing, you know, sitting there watching the data come down and watching us analyze it and see the IDs pop up, just because it's not a capability we've ever had. Host: Yeah. So you're basically scrubbing the station and putting it into here, hey, is this going to hurt me. And then you put it through the DNA sequencer, and you can find out pretty quickly, no, I'm good. Sarah Wallace: Yep. Host: And that's really the benefit rather than waiting for a return mission. Sarah Wallace: Exactly. Exactly. Host: Okay, yeah. Sarah Wallace: Yep, because imagine if you're not on ISS, and you have a limited supply of antibiotics -- Host: Yeah. Sarah Wallace: If you have a wound infection, do you treat it with the antibiotic, because maybe it's something we need to worry about. Or, is it an acne-causing bacteria? Like, don't waste the antibiotic. Let's save it. Because we can't resupply. And same thing with the disinfectant wipe. If something's growing up on station, which we've seen it, do we need to waste all of our disinfectant wipes to go clean that up? Or is it something that we don't need to worry about until later down the road? So it's really those types of questions that we get into that I think the sequencer is going to be hugely powerful in helping us address. Host: Yeah, just basic, yeah, okay, I can coexist with this for a while. It's not going to hurt me. But then also, identifying okay, this, if I have this particular type of bacteria, now you're talking about efficiency of pharmaceuticals. You're talking about, you don't waste, don't waste this one, because it's not going to work. Because the DNA sequencer identified it as this, therefore, you need to use this pharmaceutical. Sarah Wallace: Different, yep. Host: Wow, that's significant. Sarah Wallace: Yeah, and it's just, you know, and this is, again, this is all very micro-specific, because that's what I do. But those things we talked about early on, that's really the research is starting to be there on the human health front. You know, how are humans responding to things and, you know, measuring changes in the crew members' gene expression and things like that that really, you know, I think, so much beyond just microbes. But for now, the microbe part for me is just huge and exciting. Host: You're right, there's those steps, right. Let's deal with the microbe now, but then eventually, we'll be able to identify, that's Sarah Wallace. Sarah Wallace: Yep. Host: We'll get there. You know, we sort of addressed it in the beginning, but I don't think I circled back to it. One of the main things for the MinION is what you called it right, whenever you were first testing it on board the station was to see does this thing work in microgravity. Sarah Wallace: Correct. Host: So, what were the concerns that it wouldn't? Sarah Wallace: Well, everything, the way that the sequencer works, your DNA is in a fluid. It's in a buffer. And there's some salts, some other things that, there's, that when you turn on the sequencer, basically these things start to flow through these proteins. These are actual proteins. We call them nanopores. So it's a nanopore sequencer. So they're the same type of proteins that your cells have and my cells have that let ions in and out of our cells. It's those same proteins in a membrane. And as the DNA, well, let me back up, as those salts that are in the buffer flow through there, a current is created. As the DNA molecule passes through, it changes that current. It's the change in current that the software then takes and changes it into the AGTC sequence that we're looking for. So with that, the fluid and the buffers, all of that, any time there's fluidics involved, you never quite know in microgravity. Host: Yes. Sarah Wallace: On the ground, we have issues where if accidently when you're loading your sample a bubble is introduced, that bubble is very problematic. Was that going to be the same in space? So it was some very, pretty simple fundamental questions in terms of just the operation of such a small device and, you know, the crew working on a small scale. Then back to kind of the fluidics issues with bubbles, things that we just really didn't know until we got it up there. Host: Yeah, one of the things I always go back to with fluids is, I mean, if you just see any video of water is space, it's one of the coolest things to watch. Sarah Wallace: Yep. Host: Because you think, the primary force on Earth that controls water is gravity. That's what helps it stick to a cup. But at the same time, you're going to get little sweat beads, and that's the surface tension. Surface tension dominates in microgravity. Sarah Wallace: Yep. Host: And I could see that really, really messing with, but I mean, so you said you didn't have any problems. How much of it was because you had Kate Rubins, who's an expert in this sort of thing, dealing with it versus the capability of the machine. If you said everything's working perfectly, I'm thinking it's the latter. Sarah Wallace: I think, I think it's the latter as well. Host: Yeah. Sarah Wallace: I think that, right now we've been so fortunate. We've had Kate Rubins and then Peggy Whitson. Host: Yeah. Sarah Wallace: So couldn't, yeah, couldn't ask for better hands in terms of come from a lab. I mean, that's what, these are scientists. Host: They're scientists. Sarah Wallace: That's what they do. Host: Right. Sarah Wallace: So for them, it wasn't a foreign thing. We have, again, microgravity isn't at play here, but we have had multiple astronauts test this for the last two NEEMO expeditions, which is the NEEMO is a, it's Nasa Extreme Environment Mission Operations. So it's Florida International University owns this habitat that sits on the ocean floor off the coasts of Key Largo. Host: Aquarius. Sarah Wallace: There we go. Host: Yeah. Sarah Wallace: Thank you. And every, NASA rents it out for a couple weeks during the summer to send some of their astronauts to train. So last two summers we've had a lot of different astronauts get their hands on it from this, so we've actually had far more than just Kate and Peggy run the sequencer. And in extreme environment, we just haven't, we're working on writing up those papers, and they just haven't gotten talked as much about. But I think that speaks to the, just the device itself and how well it was designed, that it really is, we're doing something very, very complex. But the system is pretty simple to use, and then I like to think that the process that we've developed to do the sample prep is also pretty simple. Of course, there's, we're trying to make it better and even more simple and more automated. But it's working, and we're really excited to see where it all goes. Host: So what were they identifying in Aquarius? Were they scrubbing like the ocean floor or something? Sarah Wallace: So here's the kicker with this. So we are still focused on the inside of the habitat. Host: Yeah. Sarah Wallace: But what we were doing was we were having the crew swab a surface. That swab was going directly into the process. So we were removing the need to first culture the microorganisms. So how great would that be if we didn't, if we have potential pathogens, if the crew never has to turn them from, you know, a couple hundred maybe on the surface to millions. And we could remove that step completely. And so what we do right now is a culture-dependent process. What I hope to see in the future is a culture independent process. That's what we've been working on getting ready at NEEMO for our next spaceflight investigation. Host: So I might be missing a step. Is this that PCR component where you're making a lot of copies and -- Sarah Wallace: Kind of. Host: Okay, okay. Sarah Wallace: So we'll still need PCR, but PCR you can think of PCR as copying the DNA. Host: I see. Sarah Wallace: That culture, you can think of the actual, they're growing. They're living, they're growing, those cells are dividing. So you're amplifying the material, but those cells are living, you get the big fuzzy spots from the fungus and the big colonies from the bacteria. So removing that part. So you would still amplify the DNA, but you would never have to increase the number of organisms that you had originally in your sample, Which culture, that's what you're doing, you're increasing the number of living organisms. Host: Okay, what's the, is there a fancy culturing process in order to make sure that these things, or is it just, what do you do to culture them? To make sure that they go through this process. Sarah Wallace: That's, it's the same way, it is good old microbiology 101. The same way, if you ever took a class where you went and streaked something out and streaked it across the plate, that's the exact same thing the astronauts are doing. Host: That's what you're doing. Okay. Sarah Wallace: There's, picture a petri dish with the food in there, and that's the same thing. So it's the way microbiology has been done since the beginning. The way we've been doing microbiology since Apollo. Host: Wow. Sarah Wallace: It's great. It's the gold standard. It's you know what you have, you know. There are some drawbacks, as are with anything. And I just think moving away and not needing to do that in the future would be huge. Host: Yeah. It seems like there's a lot of microbiology components to flying in space that maybe you wouldn't normally think about. Sarah Wallace: I think, yeah, I think we're a little underrated. I don't think people think enough about us. There are, I mean, and it's, I think a lot of people, you know, take it for granted. We, you know, keeping the crew safe and healthy is what everybody who works for NASA in some way, shape or form is, that's what we care about. But if anybody's ever, you know, you've had strep throat, you've had, you know, something, a cut that gets infected. You know, you've been plagued by these things. Host: Yeah. Sarah Wallace: Infectious disease is an issue that everybody has dealt with. And just because we send astronauts up there, they may not be exposed to the flu virus or the cold virus as often as we are, but they're carrying up those bacteria and things with them that could potentially make them sick. Host: That's right. And how cool would it be if you can just use this mini PCR, and you have a little bit of a cough. And you take a little swab and put it into the mini PCR, and you're like okay, this is this kind of flu or common cold or something. And then okay, I need to take these antibiotics or something. Sarah Wallace: That's my goal. So the two-part. You do that, you just, whether it's a swab or, you know, you just something into mini PCR and then into the MinION. So we amplify it, and then we sequence. Host: Amplify, sequence. Sarah Wallace: And then that will give, and that's, we're doing that right now with just the swab. So I can envision it, you know, as the technology becomes more sensitive and we start to understand this kind of culture-independent data better, and develop proper standards and controls, I can really see it going in that direction. Host: So you talked about Genes in Space-3. And I know there's been more. So what's the sort of progress that you're taking to learn more and more about this study? Sarah Wallace: So, the biomolecule sequencer was the first. Host: Okay. Sarah Wallace: That's the, we're going to, that's what we called the MinION. That is the actual, is the company name of the sequencer. We call it the biomolecule sequencer. Host: It's a commercial off-the-shelf product, right? Sarah Wallace: Exactly. Host: Okay. Sarah Wallace: Oxford Nanopore Technologies and really the only sequencer out there that I can put in my pocket and fly to ISS. You know, it's really that small. Host: Wow. Sarah Wallace: And it's smaller than your smartphone. So the other, and then mini PCR is also extremely small. So the first one was just a biomolecule sequencer. Genes in Space at the time, we were not collaborating with them. That was a high school student's experiment, just to show same thing, DNA can be amplified in space. Host: Right. Sarah Wallace: And then we collaborated, and that was Genes in Space-3. And we're continuing our collaborations. The next investigation is called BEST, the BEST experiment. Host: Very humble. Sarah Wallace: Right. Stands for Biomolecule Extraction and Sequencing Technology. Really, what we're going to do with that is just everything we can. We're going to take advantage while we have a little bit left of this extra crew time, of this crew member, we're going to take advantage of as much science as we can get done. So that swab process I as talking about, where we just have them swab and stick that swab directly into the process, never culture anything. We're going to try that out. We are also going to do some evolution-type experiments. We're going to send up some bacteria that are common water bacteria that, you know, no one, that are very, they're safe to handle. Send them up and have them grow and then have the crew do some transfers of them. So we get a lot of generations of them reproducing. And see if we can start to see by sequencing their entire genome, see if we can start to see any changes due to mutation. And so this is something that, you know, a lot of people have been working on trying to define a mutation rate. It's hard if you don't have a proper ground control where you're tracking the same thing. And so people ask me all the time as a microbiologist, well, do things mutate? I don't know, because the staph aureus that we isolated from the Space Station, I don't have that exact staph aureus before it launched. So I can't say if it mutated. But this, we will have, we'll be able to start to get some insight into maybe how susceptible, at least this organism, is to radiation and if we can see any changes at the level of the genome. So then the next experiment, and I'm equally excited about all of them, but I'm very much excited about this one. Host: You can tell. Sarah Wallace: We will be sequencing RNA directly. This is a big deal because this is really the only platform out there that you can do direct RNA sequencing. Most of the time, you're converting RNA back into cDNA to be able to sequence it when you're doing these types of experiments. But with the Nanopore sequencer, we can sequence RNA directly, meaning we don't have to do a lot of things to change it. So I'll tell you why this is important. You yourself have your DNA in you right now that is, it says who you are, and it makes you up. But it doesn't tell me anything about what you are experiencing right now. If I'm just looking at the DNA, actually there are ways that it could tell me some things. But we'll keep it simple. So, but if I want to know things about how you're responding to your environment, I want to know what genes are being turned on and turned off. Because let's just say you have 100 genes. You have much more than that, but let's say you have 100. You don't need all 100 all the time, so your body is not going to waste energy expressing all 100 all the time. So maybe right now, sitting here talking to me, you're just trying to keep your eyes open, so you're only using those 20 to do that. Host: I'm trying to pretend I'm smart. That's what I'm doing right now. Sarah Wallace: You're doing a great job. So if I wanted to know that this environment of me talking to you is doing, I would want to know which genes are turned on and turned off. Host: Okay. Sarah Wallace: In space, that is kind of the goal is how are organisms, how are living things responding to space. And how we do that is looking at what genes are on and what genes are off. So to turn a gene on and off, you transcribe it into RNA. So that DNA makes RNA, which eventually goes on to make a protein, which will do something. But it's that RNA that's telling, that we can look at and see what kind of environment you're in. So we know the gene expression changes. Every time we've done a spaceflight experiment or we look at a living thing, we see their gene expression changing. That's just, it does because you're in a, you need certain things in space. Certain genes need to be on and off that aren't the same as they would be on Earth. Whether it's due to radiation or microgravity or you're changing your diet. All of these things. We're really now just trying to understand all this and pick it apart. So if I have a capability to where I can sequence RNA directly without having to turn it back into cDNA, which we do for most of the sequencers on Earth, and I can do it right there, I can gain a lot of insight into how these things are responding and when. And it's really important, because they change over time. And so to be able to track that and do it would give us just a huge amount of insight that we haven't had. So with this experiment, that's what we're going to do is we're going to sequence RNA directly and actually have the crew, RNA is a little less stable than DNA. It's a little bit more difficult to work with. So have the crew go through all the steps of preparing it and sequencing it. Host: So I'm trying to think of an example to sort of wrap my brain around this. So if you were to swab, I guess, some of the microbiome [phonetic] in this station, right, and then we'll just say the DNA would tell you this is kind of microbiome it is. What would it say, what would the RNA tell you about how it's reacting? What do you expect? Sarah Wallace: That's what it was. So the DNA would tell me who is there. Host: Yes. Sarah Wallace: The RNA would tell me what genes were being turned on and turned off. So it would tell me what that system, as the whole, what they are doing. So are they metabolizing the surface that they're on? Are they being able to, are they producing, are they giving off some kind of, you know, different compound? Or is it just a simple, are they just respiring? So it would tell us the function more what they are doing. It gives more towards that functionality. And so, with our cells, it tells us, again, are you able, are you building up muscle? Are you tearing down muscle? Are you, those types of things that -- Host: Wow. Sarah Wallace: Yeah. To really get at what's going on in the whole system. Aaron is my analogy guy. I should have asked him for a good analogy. Host: That's a great analogy. Sarah Wallace: He's good. But that's, it's really, it's what, the DNA tells you what capabilities are there. The RNA tells you what's actually happening. Host: So it's like, okay, so I'm going to scale it up a bit to humans. And tell me if I'm wrong again. Sarah Wallace: Okay. Host: So, the DNA would tell you, this is, let's just say Gary's flying in space. This is Gary. He has brown hair and, you know, brown eyes, and he's this tall. That's what the DNA tells you. The RNA is going to tell you he is losing muscle in this area. His eyes are changing this way, and he's kind of nervous and scared about doing this podcast. Sarah Wallace: Yes. Host: Yes, that's what it would tell you. Sarah Wallace: There we go. Yes. Host: Okay, good. Sarah Wallace: Yes. And all those little things about, all those different systems and how they're functioning together and separately, you know, and just how everything you said. Host: Okay. All right. Very interesting stuff, and especially there's a lot of applications that can go forward. I did want to circle back to just microbiology and you. How did you sort of get into this world that turned from microbiology to space microbiology? Sarah Wallace: So it all started space for me. I'm one of -- Host: Space first, okay. Sarah Wallace: I'm one of those, yep. So I am very fortunate to have grown up in a small town in Kansas. That small town in Kansas was located within about an hour drive to another small town in Kansas, Hutchinson, Kansas, which is home to the Kansas Cosmosphere and Space Center. I tell everybody if you're a space nerd, you have to go there. It's the largest collection of spaceflight memorabilia anywhere in the world, both US and Soviet at the time, Russia now. Just a phenomenal collection. Apollo 13 is there. I think the Liberty Bell is traveling around, but it was there. It's where we're sending pieces of mission control to get restored. So it really, it really is like, this is where you go to nerd out. Host: Yeah, that'll get you into space. Sarah Wallace: And they had a space camp, so I know it's not the space camp in Huntsville. But I went to that space camp. And so, just really, my sixth grade science teacher, Jim Lester, just really, he inspired the love of space in me. And not only did we take tests over, you know, the solar system, like all sixth graders do, but we took tests over NASA history. And I just loved it. So, when I, it was really when I got to undergrad, I knew, I was always a biology girl. I was never that strong in math and engineering, so thank goodness that I didn't need to do a whole lot of it. I had to do well in those classes to do well to get into graduate school. Host: Yep. Sarah Wallace: But my strength was always more in the life sciences in biology and chemistry. And so when I got into undergrad, I really, I didn't know, but there was a professor there that had some NASA funding doing kind of astrobiology-type work. And he was like, come work in my lab for a little while, and that's where I streaked my first plate as a microbiologist, and that was it. I was hooked from that day. And so, it was like how do I combine my love of microbiology with my love of NASA? And I found the University of Texas medial branch down in Galveston, which has a phenomenal PhD program in microbiology in case the whole space thing didn't work out, I would have a microbiology, you know, degree from a good world-renowned program. So I was fortunate enough to, and then have that proximity, so was able to get a fellowship to do my research, my PhD research here at NASA. And then just never left. Host: Yeah. You know, I hear that narrative a lot where you go for something knowing that if you were to just stay there, you'd be happy anyway. I see that all the time. And I think it's such a good piece of advice, because if your ultimate goal is astronaut, which it is for a lot of people. Sarah Wallace: It is for a lot of people. Host: You know, you've got to take steps that if you were to no get to eventually astronaut, you would be happy for the rest of your life in whatever. I love that, yeah. I think it's a good piece of advice. Sarah Wallace: Great plan B. Host: Yeah. Sarah Wallace: And also, you know, STEM is so important, but I always tell kids, you have to be good in all of them. Find the one you're passionate about, and if you struggle as you get into some of the harder math classes, that's okay. Host: Yeah. Sarah Wallace: Or if you struggle in, you know, you don't care about the biology, but you really like the chemistry. Whatever it is, you know, I just I think that's good too. Host: Just hang in there until you swab a plate. Sarah Wallace: Exactly. And once, it's magic once that happens. Host: I love it. I love it. You know, talking about, you know, passion for space and sort of going down this path to eventually do microbiology for NASA, there's one story that's just, it's stuck in my head. And that's last year when Hurricane Harvey happened, and gosh darn we still needed to sequence that DNA in space, you were calling Peggy Whitson from your house because we were all trapped because of the storm. Sarah Wallace: Yes. Host: How was that experience? Sarah Wallace: That, I was going to say, getting the data was probably the highlight of my life. That actually was probably the highlight of my life. So, the way we did Genes in Space-3, we did it in two separate portions so that it would be just easier to schedule and that kind of thing. So, the first part was to have Peggy collect some of those cells that were growing and put them in mini PCR. And then it can stop, and after that point, whenever there was time again, to come back and collect that. There was a little more prep she had to do to sequence it. So come back, get the DNA that had been amplified, and then finish prepping it for sequence and actually sequencing. So we had done the first part a week or two before Harvey hit. Everything went well. But of course, I'm just waiting, like knowing it's so close. Let's get these IDs. So, it gets put on the timeline for that Monday morning, and Harvey hits. And it became very apparent that the, the Center, it wasn't like you could come in. It was like you're not coming in. The Center was closed, and -- Host: The gates were under water. Sarah Wallace: Yes. Host: You literally like could not physically couldn't. Sarah Wallace: I could not. I could not leave my house. Host: Yeah, yeah. Sarah Wallace: It was awful for anyone that lives here understands. So, but me, you know, yes I'm worried about the house and the cars and all those things, my family. Should have said that first. But you know, for me it was like, we have the schedule, you know, the crew's up there. They're still doing their stuff. We need to support. So I'm usually enabled to talk them through the procedures just in case they have any questions or anything. So I usually communicate with them. I had taken my, everything home to be able to connect to the voice loops that allow us to communicate with the crew. But of course, my, the firewall was blocking my connection for my internet from home. So that's when the people at Marshall Space Flight Center, the POIC folks were like, that's it. We'll patch you through to Peggy. And Peggy, she didn't know, she just thought I was talking to her like normal. But I'm in my house, in my sweatshirt, and it's raining and cold, and on my cellphone. And I usually have video. I can usually see what the astronauts were doing. This time I did not. I was blind. Host: Wow. Sarah Wallace: So I was really, I had my procedure book. I knew where she was in the process. I knew what she was doing, so I was able to walk her through it. Went off without a hitch, like thank goodness there were no weird things that had to be troubleshooted. Everything went perfectly. And as the sequencer, what's really cool about the sequencer is as it's sequencing, you're getting the data near real time. So, I don't know if things are successful. I know what Peggy's told me. But the folks at Marshall were able to get a camera view on the Surface Pro 3 that we had running the sequencer. And they were able to get a screen shot of me that confirmed to me that it was successful. So, we knew pretty soon after Peggy had hit go on the sequencer that it was at least sequencing something that was the size of the gene we were looking to sequence. And so, that was just, that was one of the most exciting moments. And when I got that text from Marshall with that picture, I sent to, you know, my whole team. And it was just a super, super exciting moment. And it really was. It was like this, you know, not only this experiment but just science in general was not stopped because of Hurricane Harvey. And I just think that that's, being here in Houston, and I just, I think that's such a cool story. And for me personally, just because it was a huge, a huge first in space. You know, if you think about what we were doing, we took bacteria that had been collected from and cultured entirely in space, and then we sequenced them and got the AD entirely in space. So we did all of this that normally takes the whole lab off of the planet. And I mean, it was just a big huge first, and we're really excited. Host: And you still got the data in your living room on a cellphone. Sarah Wallace: Yep. Host: And like you said, doing it blind. Sarah Wallace: Yep. Host: Doing it, just reading the procedures, not getting a video feed. Sarah Wallace: Yep. Host: That's a testament to the technology, but then also, just the communications from mission control. It's a, that's a huge accomplishment really. Sarah Wallace: Thanks. And the people at Marshall, like they were, they knew that, you know, they're always running the payloads, but they knew that time especially that there just wasn't anything we could do from here. So they were awesome. Host: Yeah. Now really, I absolutely love that story. It's really, really cool. I wanted to kind of end with sort of looking ahead. You know, we're talking about a lot of stuff going on the Station, and we've definitely hinted in the beginning of the evolution of what's possible with DNA and RNA sequencing. There's just, there's so much ahead. What are some of the implications whenever we are starting to go beyond lower Earth orbit and starting to travel now deeper into space? Now you're talking about transiting to Mars on, you know, several month, several year-long missions. You're talking about going to the moon and even beyond, you know, thinking really way ahead. How is DNA sequencing and RNA sequencing really going to help you along the way? Sarah Wallace: So I think for me personally, it's going to be, it's all about the microbes. It's being able to know if a crew member has an infectious disease that we can diagnose it. If their vehicle has something, we can diagnose it. And then we can provide the proper course of remediation. Which if we're far away from Earth, that's going to be really critical that we get that data. For my friends that work on more the side of the humans and not just the microbes, I really think what we're going to start seeing is the use of this technology to monitor the way humans are responding to spaceflight, in whatever it is, if it's in terms of a certain, you know, the diet that they're eating or an exercise, you know, regime that they're doing. Whatever it is, how are they responding to it? And is it the way we think, or should it be altered and tweaked? That's the kind of thing that I'm seeing now being done, research here on Earth that, you know, hopefully it can start to be applied to NASA. And I know many of my colleagues are looking at that to really have that, you know, how is astronaut Gary responding? What do we need to do to make his response better, healthier, stronger, all of those things? Then on the turn of that, I would be remiss if I didn't mention this. So I mentioned my colleague, Dr. Aaron Burton who is the PI of the biomolecule sequencer. Host: Right. Sarah Wallace: So for me, the sequencer is the here and now with the microbes. For him, it really is this future. Is this device a first-generation device that is along the lines of what some day detects life beyond Earth? And why we're so excited about the sequencer is because, as I was describing the way it worked with that change in current. So it's not detecting DNA or RNA per se. It's detecting a biomolecule that's going through its pore. It can be anything that's going through that pore. You just need to know what the signature is and have your database to be able to match it up to. So he has colleagues, and they're working on things that are, you know, it's not like DNA or RNA as we know it. They call it XNAs, and it's something that maybe, if life weren't like what we expect it to be, this technology could detect it. So it's far out there, but you know, it's really not that far out there. If maybe this is version one of what that device some day is. Host: Yeah. Sarah Wallace: So to be able to detect life beyond Earth, and you know, have this thing strapped to a rover or in an astronaut's hand on another planet, I think, is something that's definitely the something that folks in the astrobiology world are really excited about. Host: Yeah, maybe not identify right off the bat, but at least start to identify -- Sarah Wallace: Right. Host: and realize what this is, because. Sarah Wallace: So, just having something that you knew came from biological origin. It wasn't, you know, it came from something living, it is truly a biomolecule. Not just, you know, oh we found amino acid, but it didn't come from something living. No, this was from something living. Host: Yeah. And it has to, does some of it have to do with, and this can be a whole tangent of a conversation, but, you know, when we're talking about DNA and RNA and identifying these proteins, there's a difference between these proteins. Which I think, I forget which one, but there's a difference between left-handed and right-handed, and all the ones on Earth are one of the two, I forget. Sarah Wallace: Yes. Host: If they're left-handed or right-handed. I think left-handed proteins. Sarah Wallace: I'm not going to jump in there. Host: Okay, yeah. Sarah Wallace: And that is, that's out, if you want to do another one on taking that spin, you need Aaron Burton. That's what he does. Host: Right. Sarah Wallace: So yeah, but yes. Host: Okay. Sarah Wallace: And that's, you know. Host: Is that that XNA kind of going down that path. Sarah Wallace: So kind of. It's just, it's not the, you know, it may not be the AGTC that we're so used to seeing. It might be something totally different. Host: Yeah. Sarah Wallace: And this, this technology could detect it. And so there's researchers out there working on ways to, you know, throw anything you can at it and see what it can detect. And also, you know, making it more robust and durable to survive a trip to Enceladus or Europa, or you know, wherever they're going. So, but I leave all that to Aaron. So. Host: Yeah. Sarah Wallace: He can give you good answers there. Host: I just think this is a fascinating topic, not only because of what we're doing right now but then exactly what we're talking about now, what we can do in the future. For space exploration, but then also, kind of bringing it down to Earth. Sarah Wallace: Yes. Host: That would be huge if you can identify like an illness, like right off the bat, and know exactly how to treat that. There's some significant Earth benefits. Sarah Wallace: Yeah, can you imagine going to your doctor's office and right away walking away with a confirmed, it's you know, it's this. You need, you know, it's a staph infection. But not only is it I staph infection, it's resistant to these, these, these antibiotics. So we're putting you on this antibiotic. Knowing that. Just like walking away and knowing that, not needing further tests or anything like that. I really think that's kind of what this, the ease and the portability of use of this technology, I really think that's a great prime target for them is really. And I think you're going to see, you know, you're going to go to your doctor and they're, well let's just take a look at your whole genome and let's see if you are, you know, it's. You can pay right now to have it done for fun, you know, the 23 and Me. Host: Oh yeah. Sarah Wallace: But it's really, I think, might be coming. And then that gets into all kinds of ethical things. But, you know. Host: Sure. Oh yeah, if you want gene editing, and that's a whole different, that's one of those other tangents we can take and do a whole other episode. Sarah Wallace: And human genetic data is, which I love sticking with the microbes. Host: Yeah, yeah. Sarah Wallace: Yeah. All kinds of issues when you start talking about human data. Host: Well still some breakthrough stuff just going on in the world in microbes. Sarah Wallace: Absolutely. Host: Yeah, yeah. Sarah Wallace: And they're, you know, like we talked about earlier. We, it's an important thing that we do, you know. It's, if anybody's ever really had a bad night in the restroom because of food poisoning or something along those lines, and knows how extreme it can be, it's not something we want the crew to experience. Host: Oh, for sure. Sarah Wallace: And that's just one example. Host: Yeah. Well Sarah, I really just wanted to thank you for your contribution to the space program. But I'm sure you're not the only one making all these breakthroughs, are you? Sarah Wallace: Yep, no. As I've said, my colleague Dr. Aaron Burton was the PI originally, and he's still, it's really, there's been a team of four of us all the way through. So Aaron Burton, Kristen John, Sarah Stahl and myself. So really, the four of us, we've had lots of other collaborators. But we've been the four key people who have done all of this. Host: Wow. Just that small of a team making these -- Sarah Wallace: We're a small team. Host: Yeah. Sarah Wallace: Yeah. Host: Well, hey, thank you so much for your contributions. Again, to the whole team, but also to you, Sarah, for coming on the podcast today. Sarah Wallace: Thank you very much. [ Music ] Host: Hey, thanks for sticking around. So today we talked to Dr. Sarah Wallace about sequencing DNA and RNA in space. This was episode 49 of Houston We Have a Podcast, but they're not really in any particular order. So you can go back and listen to another episode if you want. We talked a little bit about Dr. Aaron Burton. And that was an episode called The Search for Life. You can go back and listen to when we're talking, we almost went on a tangent about the difference between left-handed proteins and right-handed proteins. We get into that a little bit in that episode The Search for Life. You can go back and listen to that. They're in no particular order. So trust me, all of them are good. And this was from a completely unbiased opinion. Otherwise, you can listen to other NASA podcasts. We have Gravity Assist up at headquarters hosted by Dr. Jim Green, if you're really into planetary science. Otherwise, we have our friends over at the Ames Research Center that have the podcast called NASA in Silicon Valley that talk about the things they're doing over there in California. And they also do some of the research aboard the International Space Station just like we do here at the Johnson Space Center. And we also talked about during this podcast our friends over at the Marshall Space Flight Center over in Huntsville, Alabama do. It's sort of a cross-center thing. But you can see some of the things that they're doing over there. If you want to know what's going on aboard the International Space Station besides DNA sequencing, NASA.gov/iss is a great place to do that. Otherwise, NASA.gov/hrp is a good place to see some of the other human research program elements that we're doing. Dr. Sarah Wallace is part of the microbiology lab here, and there's a lot of other human research aspects to, I guess, just flying humans in space but also aboard the International Space Station and beyond. On social media, we're on the International Space Station account. You guys should know this, Facebook, Twitter and Instagram. Go to any one of those accounts and use the hashtag ask NASA on any one of the platforms to submit an idea for the podcast. And then we'll make sure to mention it on a future episode or make a whole episode out of it. This podcast was recorded on April 17, 2018. Thanks to Alex Perryman, Isidro Reyna., Pat Ryan, Bill Stafford and Junie Hayes [phonetic]. And special thanks to Thalia Petrinos [phonetic] for writing the questions on today's episode. Thanks again to Dr. Sarah Wallace for coming on the show. We'll be back next week.